Feature:1. Waterproof rings are available in various sizes to meet your different needs, suitable for different watch models.2. Covers the gaps between the strap and the movement, making the watch waterproof, wonderful watch repairing parts.3. Made of high quality plastic material, long service life, durable and practical, not easy to damage.4. Professional watch maintenance tools, watch repairing and DIY watchmaker excellent accessories.5. O‑Ring back gasket kit, wonderful replacement for the old and broken one, directly fitment.How to Use:Use the watch cover opening tool to open the back cover of the watch, put the waterproof ring in and then close the back cover of the watch.Specification:Item Type: Waterproof O RingMaterial: PlasticApplicable People: Watch maintenance professionalsApplication Scenario: Used to add waterproof ring to the watch or replace the waterproof ring 8.5 x 45 x 90mm / 0.33 x 1.77 x 3.54in 9.5 x 45 x 90mm / 0.37 x 1.77 x 3.54in 11 x 45 x 90mm / 0.43 x 1.77 x 3.54in 11.5 x 45 x 90mm / 0.45 x 1.77 x 3.54in 12.5 x 45 x 90mm / 0.49 x 1.77 x 3.54in 13 x 45 x 90mm / 0.51 x 1.77 x 3.54in 14 x 45 x 90mm / 0.55 x 1.77 x 3.54in 14.5 x 45 x 90mm / 0.57 x 1.77 x 3.54in 5.5 x 45 x 90mm / 0.22 x 1.77 x 3.54in 16 x 45 x 90mm / 0.63 x 1.77 x 3.54in 32 x 45 x 90mm / 1.26 x 1.77 x 3.54in 32.5 x 45 x 90mm / 1.28 x 1.77 x 3.54in 33.5 x 45 x 90mm / 1.32 x 1.77 x 3.54in 34 x 45 x 90mm / 1.34 x 1.77 x 3.54in 35 x 45 x 90mm / 1.38 x 1.77 x 3.54in 35.5 x 45 x 90mm / 1.4 x 1.77 x 3.54in 17.5 x 45 x 90mm / 0.69 x 1.77 x 3.54in 18 x 45 x 90mm / 0.71 x 1.77 x 3.54in 19 x 45 x 90mm / 0.75 x 1.77 x 3.54in 19.5 x 45 x 90mm