Features 1、Water Resistant: The plastic o ring watch gasket is installed in the back cover of the watch and covers the gaps between the strap and the movement. This plastic gasket kit plays a important role in the water proof function of the watch. 2、Material: Made of abrasion resistant, flexible plastic material, the watch washer provides excellent water and oil resistant and sealing properties, and can withstand high temperature environments. Its O ring sealed design can be applied for line wiring maintenance, preventing unwanted touching, effectively protecting the watch and facilitating fastening. 3、Quantity: Includes 49 models of back cover seals, each size has 1 piece, can meet your watch maintenance and repair work of various sizes needs, to ensure its excellent sealing and protecting performance. 4、Replacement Set: Excellent replacement for watch back cover sealing gaskets. Its unique flexibility allows it to fit your watch seamlessly, providing stable and reliable support for watch maintenance and repair work. 5、Multifunctional: The gasket is suitable for watchmakers and watch repairers, and is also ideal for watch maintenance. Its excellent fit ensures that it can be easily installed on a variety of watch back covers, helping you keep your watch in great condition. Specification Item Type: Watch Gasket Material: Plastic Water Proof Ring Model: Approx. 16mm-40mm / 0.63-1.57in Package List 49 x Water Proof Ring<br>1 x Plastic Box