Catalogue

Expand all | Collapse all | Show hidden lines

  • Banner

ELRING 949.740 Seal Ring

949.740
£0.00
Tax included
Quantity
Out-of-Stock

  Security policy

(edit with the Customer Reassurance module)

  Delivery policy

(edit with the Customer Reassurance module)

  Return policy

(edit with the Customer Reassurance module)

VOLVO
977005
Product Details
ELRING
949.740
New product

Data sheet

Shape
O-Ring
Material
HNBR (hydrogenated nitrile butadiene rubber)
Inner diameter [mm]
24
Outer diameter [mm]
30
Thickness [mm]
3
New product
100 other products in the same category:
DELCO REMY 1967037 Seal Ring Quick view

Reference: 1967037

Brand: DELCO REMY

DELCO REMY 1967037 Seal Ring

for OE number : ........,..,..,,,., Weight [g] : 3

(0)

Price £0.00
More
Out-of-Stock
ELRING 330.965 Seal Ring Quick view

Reference: 330.965

Brand: ELRING

ELRING 330.965 Seal Ring

Material : MVQ (Silicone Elastomer), Dust ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 311.940 Seal Ring Quick view

Reference: 311.940

Brand: ELRING

ELRING 311.940 Seal Ring

Material : FPM (fluoride rubber)/ACM ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 393.830 Seal Ring Quick view

Reference: 393.830

Brand: ELRING

ELRING 393.830 Seal Ring

Shape : O-Ring, Material : MVQ (Silicone ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 559.030 Seal Ring Quick view

Reference: 559.030

Brand: ELRING

ELRING 559.030 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 457.620 Seal Ring Quick view

Reference: 457.620

Brand: ELRING

ELRING 457.620 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 545.750 Seal Ring Quick view

Reference: 545.750

Brand: ELRING

ELRING 545.750 Seal Ring

Shape : A-shape, Material : NBR (nitrile ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 728.880 Seal Ring Quick view

Reference: 728.880

Brand: ELRING

ELRING 728.880 Seal Ring

Supplementary Article/Info 2 : with mounting ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 152.320 Seal Ring Quick view

Reference: 152.320

Brand: ELRING

ELRING 152.320 Seal Ring

Material : PTFE (polytetrafluoroethylene)/ACM ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 584.630 Seal Ring Quick view

Reference: 584.630

Brand: ELRING

ELRING 584.630 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 332.670 Seal Ring Quick view

Reference: 332.670

Brand: ELRING

ELRING 332.670 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 553.272 Seal Ring Quick view

Reference: 553.272

Brand: ELRING

ELRING 553.272 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 147.670 Seal Ring Quick view

Reference: 147.670

Brand: ELRING

ELRING 147.670 Seal Ring

Colour : Green, Shape : O-Ring, Material : FPM ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 612.103 Seal Ring Quick view

Reference: 612.103

Brand: ELRING

ELRING 612.103 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 561.960 Seal Ring Quick view

Reference: 561.960

Brand: ELRING

ELRING 561.960 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 339.480 Seal Ring Quick view

Reference: 339.480

Brand: ELRING

ELRING 339.480 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 821.390 Seal Ring Quick view

Reference: 821.390

Brand: ELRING

ELRING 821.390 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 044.598 Seal Ring Quick view

Reference: 044.598

Brand: ELRING

ELRING 044.598 Seal Ring

Material : MVQ (Silicone Elastomer), Dust ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 901.560 Seal Ring Quick view

Reference: 901.560

Brand: ELRING

ELRING 901.560 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 504.581 Seal Ring Quick view

Reference: 504.581

Brand: ELRING

ELRING 504.581 Seal Ring

Fitting Position : Left, Material : FPM ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 801.231 Seal Ring Quick view

Reference: 801.231

Brand: ELRING

ELRING 801.231 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 113.107 Seal Ring Quick view

Reference: 113.107

Brand: ELRING

ELRING 113.107 Seal Ring

Shape : A-shape, Material : Copper, Inner ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 002.820 Seal Ring Quick view

Reference: 002.820

Brand: ELRING

ELRING 002.820 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 244.848 Seal Ring Quick view

Reference: 244.848

Brand: ELRING

ELRING 244.848 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 327.255 Seal Ring Quick view

Reference: 327.255

Brand: ELRING

ELRING 327.255 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 165.990 Seal Ring Quick view

Reference: 165.990

Brand: ELRING

ELRING 165.990 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 906.060 Seal Ring Quick view

Reference: 906.060

Brand: ELRING

ELRING 906.060 Seal Ring

Material : ACM (Polyacrylate), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 046.264 Seal Ring Quick view

Reference: 046.264

Brand: ELRING

ELRING 046.264 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
DELCO REMY 1941042 Seal Ring Quick view

Reference: 1941042

Brand: DELCO REMY

DELCO REMY 1941042 Seal Ring

for OE number : .........,,.,,,,,,

(0)

Price £0.00
More
Out-of-Stock
ELRING 535.250 Seal Ring Quick view

Reference: 535.250

Brand: ELRING

ELRING 535.250 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 938.260 Seal Ring Quick view

Reference: 938.260

Brand: ELRING

ELRING 938.260 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 294.430 Seal Ring Quick view

Reference: 294.430

Brand: ELRING

ELRING 294.430 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 290.710 Seal Ring Quick view

Reference: 290.710

Brand: ELRING

ELRING 290.710 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 766.402 Seal Ring Quick view

Reference: 766.402

Brand: ELRING

ELRING 766.402 Seal Ring

Material : FPM (fluoride rubber)

(0)

Price £0.00
More
Out-of-Stock
ELRING 040.142 Seal Ring Quick view

Reference: 040.142

Brand: ELRING

ELRING 040.142 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 394.012 Seal Ring Quick view

Reference: 394.012

Brand: ELRING

ELRING 394.012 Seal Ring

Supplementary Article/Info 2 : with mounting ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 315.621 Seal Ring Quick view

Reference: 315.621

Brand: ELRING

ELRING 315.621 Seal Ring

Shape : O-Ring, Material : NBR (nitrile ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 902.860 Seal Ring Quick view

Reference: 902.860

Brand: ELRING

ELRING 902.860 Seal Ring

Material : PTFE (polytetrafluoroethylene)/ACM ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 247.300 Seal Ring Quick view

Reference: 247.300

Brand: ELRING

ELRING 247.300 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 037.109 Seal Ring Quick view

Reference: 037.109

Brand: ELRING

ELRING 037.109 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 073.890 Seal Ring Quick view

Reference: 073.890

Brand: ELRING

ELRING 073.890 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 707.460 Seal Ring Quick view

Reference: 707.460

Brand: ELRING

ELRING 707.460 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 131.860 Seal Ring Quick view

Reference: 131.860

Brand: ELRING

ELRING 131.860 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 505.740 Seal Ring Quick view

Reference: 505.740

Brand: ELRING

ELRING 505.740 Seal Ring

Material : FPM (fluoride rubber)/ACM ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 242.620 Seal Ring Quick view

Reference: 242.620

Brand: ELRING

ELRING 242.620 Seal Ring

Material : PTFE (polytetrafluoroethylene), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 887.230 Seal Ring Quick view

Reference: 887.230

Brand: ELRING

ELRING 887.230 Seal Ring

Shape : A-shape, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 703.087 Seal Ring Quick view

Reference: 703.087

Brand: ELRING

ELRING 703.087 Seal Ring

Shape : O-Ring, Material : EPDM (ethylene ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 810.580 Seal Ring Quick view

Reference: 810.580

Brand: ELRING

ELRING 810.580 Seal Ring

Material : FPM (fluoro rubber)/ NBR ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 224.278 Seal Ring Quick view

Reference: 224.278

Brand: ELRING

ELRING 224.278 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 208.210 Seal Ring Quick view

Reference: 208.210

Brand: ELRING

ELRING 208.210 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 573.043 Seal Ring Quick view

Reference: 573.043

Brand: ELRING

ELRING 573.043 Seal Ring

Shape : O-Ring, Material : NBR (nitrile ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 237.744 Seal Ring Quick view

Reference: 237.744

Brand: ELRING

ELRING 237.744 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 755.478 Seal Ring Quick view

Reference: 755.478

Brand: ELRING

ELRING 755.478 Seal Ring

Shape : O-Ring, Material : NBR (nitrile ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 081.460 Seal Ring Quick view

Reference: 081.460

Brand: ELRING

ELRING 081.460 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 353.060 Seal Ring Quick view

Reference: 353.060

Brand: ELRING

ELRING 353.060 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 247.189 Seal Ring Quick view

Reference: 247.189

Brand: ELRING

ELRING 247.189 Seal Ring

Material : MVQ (Silicone Elastomer), Dust ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 022.851 Seal Ring Quick view

Reference: 022.851

Brand: ELRING

ELRING 022.851 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 655.902 Seal Ring Quick view

Reference: 655.902

Brand: ELRING

ELRING 655.902 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 284.930 Seal Ring Quick view

Reference: 284.930

Brand: ELRING

ELRING 284.930 Seal Ring

Material : PTFE (polytetrafluoroethylene)/ACM ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 151.490 Seal Ring Quick view

Reference: 151.490

Brand: ELRING

ELRING 151.490 Seal Ring

Material : MVQ (Silicone Elastomer), Dust ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 009.075 Seal Ring Quick view

Reference: 009.075

Brand: ELRING

ELRING 009.075 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 586.676 Seal Ring Quick view

Reference: 586.676

Brand: ELRING

ELRING 586.676 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 319.104 Seal Ring Quick view

Reference: 319.104

Brand: ELRING

ELRING 319.104 Seal Ring

Material : MVQ (Silicone Elastomer), Dust ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 733.130 Seal Ring Quick view

Reference: 733.130

Brand: ELRING

ELRING 733.130 Seal Ring

Material : PTFE (polytetrafluoroethylene)/ACM ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 115.606 Seal Ring Quick view

Reference: 115.606

Brand: ELRING

ELRING 115.606 Seal Ring

Shape : A-shape, Material : Copper, Inner ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 467.995 Seal Ring Quick view

Reference: 467.995

Brand: ELRING

ELRING 467.995 Seal Ring

Material : ACM (Polyacrylate), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 135.500 Seal Ring Quick view

Reference: 135.500

Brand: ELRING

ELRING 135.500 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 454.000 Seal Ring Quick view

Reference: 454.000

Brand: ELRING

ELRING 454.000 Seal Ring

Material : FPM (fluoride rubber), Height [mm] ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 509.750 Seal Ring Quick view

Reference: 509.750

Brand: ELRING

ELRING 509.750 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 092.170 Seal Ring Quick view

Reference: 092.170

Brand: ELRING

ELRING 092.170 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 507.806 Seal Ring Quick view

Reference: 507.806

Brand: ELRING

ELRING 507.806 Seal Ring

Material : FPM (fluoride rubber)/ACM ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 515.350 Seal Ring Quick view

Reference: 515.350

Brand: ELRING

ELRING 515.350 Seal Ring

Material : ACM (Polyacrylate), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 018.670 Seal Ring Quick view

Reference: 018.670

Brand: ELRING

ELRING 018.670 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 023.740 Seal Ring Quick view

Reference: 023.740

Brand: ELRING

ELRING 023.740 Seal Ring

Supplementary Article/Info 2 : with mounting ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 104.108 Seal Ring Quick view

Reference: 104.108

Brand: ELRING

ELRING 104.108 Seal Ring

Shape : A-shape, Material : Copper, Inner ...

(0)

Price £0.00
More
Out-of-Stock
DELCO REMY 1988138 Seal Ring Quick view

Reference: 1988138

Brand: DELCO REMY

DELCO REMY 1988138 Seal Ring

Component Number : 1988138

(0)

Price £0.00
More
Out-of-Stock
ELRING 578.134 Seal Ring Quick view

Reference: 578.134

Brand: ELRING

ELRING 578.134 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 524.215 Seal Ring Quick view

Reference: 524.215

Brand: ELRING

ELRING 524.215 Seal Ring

Supplementary Article/Info 2 : with mounting ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 003.970 Seal Ring Quick view

Reference: 003.970

Brand: ELRING

ELRING 003.970 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 165.991 Seal Ring Quick view

Reference: 165.991

Brand: ELRING

ELRING 165.991 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 429.060 Seal Ring Quick view

Reference: 429.060

Brand: ELRING

ELRING 429.060 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
DELCO REMY 500082 Seal Ring Quick view

Reference: 500082

Brand: DELCO REMY

DELCO REMY 500082 Seal Ring

for OE number : ........,,.,...,..

(0)

Price £0.00
More
Out-of-Stock
ELRING 038.660 Seal Ring Quick view

Reference: 038.660

Brand: ELRING

ELRING 038.660 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 659.160 Seal Ring Quick view

Reference: 659.160

Brand: ELRING

ELRING 659.160 Seal Ring

Supplementary Article/Info 2 : with mounting ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 911.230 Seal Ring Quick view

Reference: 911.230

Brand: ELRING

ELRING 911.230 Seal Ring

Colour : Purple, Shape : A-shape, Material : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 232.300 Seal Ring Quick view

Reference: 232.300

Brand: ELRING

ELRING 232.300 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 107.239 Seal Ring Quick view

Reference: 107.239

Brand: ELRING

ELRING 107.239 Seal Ring

Shape : A-shape, Material : Copper, Inner ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 587.430 Seal Ring Quick view

Reference: 587.430

Brand: ELRING

ELRING 587.430 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 029.335 Seal Ring Quick view

Reference: 029.335

Brand: ELRING

ELRING 029.335 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 141.960 Seal Ring Quick view

Reference: 141.960

Brand: ELRING

ELRING 141.960 Seal Ring

Fitting Position : Clutch side, Material : FPM ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 231.975 Seal Ring Quick view

Reference: 231.975

Brand: ELRING

ELRING 231.975 Seal Ring

Shape : O-Ring, Material : MVQ (Silicone ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 195.740 Seal Ring Quick view

Reference: 195.740

Brand: ELRING

ELRING 195.740 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 587.460 Seal Ring Quick view

Reference: 587.460

Brand: ELRING

ELRING 587.460 Seal Ring

Material : FPM (fluoride rubber)/ACM ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 135.010 Seal Ring Quick view

Reference: 135.010

Brand: ELRING

ELRING 135.010 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 447.610 Seal Ring Quick view

Reference: 447.610

Brand: ELRING

ELRING 447.610 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 155.560 Seal Ring Quick view

Reference: 155.560

Brand: ELRING

ELRING 155.560 Seal Ring

Material : PTFE (polytetrafluoroethylene)/ACM ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 220.450 Seal Ring Quick view

Reference: 220.450

Brand: ELRING

ELRING 220.450 Seal Ring

Material : NBR (nitrile butadiene rubber), ...

(0)

Price £0.00
More
Out-of-Stock
ELRING 033.472 Seal Ring Quick view

Reference: 033.472

Brand: ELRING

ELRING 033.472 Seal Ring

Material : FPM (fluoride rubber), Dust Cover : ...

(0)

Price £0.00
More
Out-of-Stock
DELCO REMY 1909498 Seal Ring Quick view

Reference: 1909498

Brand: DELCO REMY

DELCO REMY 1909498 Seal Ring

for OE number : .........,.,,,,...

(0)

Price £0.00
More
Out-of-Stock
ELRING 274.040 Seal Ring Quick view

Reference: 274.040

Brand: ELRING

ELRING 274.040 Seal Ring

Shape : O-Ring, Material : FPM (fluoride ...

(0)

Price £0.00
More
Out-of-Stock

Follow us on Facebook

Facebook