G19219 Waterproof I-ring Gasket 0.8mm 0.9mm 1.25mm 1.75mm Height for Watch Crystal 8.5mm-40mm

It is used on watch crystal, NOT Caseback! for professional users! 
You have to know the exact diameter and thickness of your watch crystal before buying.
Height 0.8mm, thickness appr. 0.35mm,  fits for 0.8-1.5mm thick watch crystal
Height 0.9mm, thickness appr. 0.45mm, fits for 1.0-1.5mm thick watch crystal
Height 1.25mm, thickness appr. 0.40mm, fits for 1.5-2.0mm thick watch crystal
Height 1.75mm, thickness appr. 0.40mm, fits for 2.0-3.0mm thick watch crystal
 
INNER Diameter:
8.5/9.5/10.5/11/11.5/12/12.5/13/13.5/14/14.5/15/15.5/16/16.5/17/17.5/18/18.5/19/19.5/20/20.5/21/21.5/22/22.5/23/23.5/24/24.5/25/25.5/26/26.5/27/27.5/28/28.5/29/29.5/30/
30.5/31/31.5/32/32.5/33/33.5/34/34.5/35/35.5/36/36.5/37/37.5/38/38.5/39/39.5/40MM
Please note that this is inner diameter, NOT outside diameter
 
1 piece per order
 
Package included: 1 piece*Waterproof I-ring