Outer diameter:6.5cm Inner diameter:6cm Height:1.9cm Thickness:0.5cm The hardness of silicone:70 Compatable with: IROBOT ROOMBA 500 505 510 520 521 530 531 532 533 534 535 536 540 545 550 552 555 560 561 562 563 564 565 570 580 581 585 587 589 595 599 600 605 610 615 616 620 621 625 630 631 632 639 650 651 660 670 680 681 700 720 750 760 765 770 772 774 775 776 780 782 785 786 800 850 860 865 866 870 871 875 876 880 886 890 900 960 965 966 976 980 E5 I7 I7 + S9 S9 + Material:Silica gel colour:Black Package Contents: 4 x Tire Strap Accessories Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-Dadangjia