Watch Gaskets Waterproof Medium O-Ring Assortment (180 Pieces)

This o-ring watch case back seal assortment is a great gasket kit for watchmakers and others who work on watch case backs. These round gaskets are made of solid tube rubber to create an airtight seal and are flexible enough to fit not only round watch case backs but, square, rectangle and other fancy shaped case backs. The thicknesses range from .50 mm to .70 mm and the inside diameters range from 15 mm to 34 mm.

• Assortment contains 60 different o-ring sizes in 3 different thicknesses
• **Note** Diameter measured is the interior diameter of the gasket
• In .50 mm thickness there are 18 different sizes: 15, 16, 17.5, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, and 32 mm
• In .60 mm thickness there are 20 different sizes: 16, 17.5, 17.9, 19, 20, 21, 22, 24.5, 25, 26, 27, 28, 29.5, 30, 31, 31.5, 32, 33, 33.8, and 34 mm
• In .70 mm thickness there are 22 different sizes: 17.5, 18, 19, 20.8, 21.5, 23, 24.5, 25, 26, 26.5, 27, 27.5, 28, 28.5, 29, 29.5, 30, 30.5, 31, 31.5, 32, and 33 mm
• Contains 3 of each size
• Can easily be reordered by size in the following format: thickness-mm diameter (50-1500)
• Refills are available in packages of 3
• Kit has a total of 180 pieces
• O-rings fit a variety of watch case backs from round to square
• Maintain airtight seal
• Medium size o-rings
• Made of rubber