1.75mm Height I Ring 16mm to 25.5mm Inner Diameter Waterproof Plastic Gasket for Watch Crystal Round Glass W4312

1.75mm Height I Ring 16mm to 25.5mm Inner Diameter Waterproof Plastic Gasket for Watch Crystal Round Glass W8146

It is used on watch crystal to make the watch waterproof, NOT watch back case cover! for professional users!you have to know the exact diameter and thickness of your watch crystal before buying.

Height 1.75mm, thickness appr. 0.40mm, fits for 2.0mm-3.0mm thick watch crystal

Diameter(Outside Diameter. X Inner Diameter.)mm Please see below

16.8X16.0,  17.3X16.5,  17.8X17.0, 18.3X17.5, 18.8X18.0, 19.3X18.5, 19.8X19.0, 20.3X19.5, 20.8X20.0, 21.3X20.5

21.8X21.0 ,  22.3X21.5,  22.8x22.0, 23.3x22.5, 23.8x23.0, 24.3X23.5, 24.8X24.0, 25.3X24.5, 25.8X25.0, 26.3X25.5

1 piece per order, please choose the diameter that you need.

Package included: 1 piece * Waterproof I-ring