Watch Case Back O-Ring Gasket Standard Pack 30 To 35mm

Mid-size watches are everywhere, and so is the need to service them. The Standard Pack is an 18-piece O-ring case back gasket assortment covering six of the most widely used watch case sizes 30mm, 31mm, 32mm, 33mm, 34mm, and 35mm with 3 gaskets per size at a reliable 0.6mm thickness.

This range sits at the heart of the watch market. Everyday wearers, entry-level automatics, popular quartz watches from Seiko, Citizen, Orient, Tissot, and countless fashion brands all use case backs in this exact size window. Therefore, whether you are servicing your own watch collection or running a small repair operation, The O-Ring Gasket 0.6mm Standard Pack gives you the most practical assortment you can own.

A failing gasket rarely announces itself. Instead, it quietly hardens and loses its seal, allowing moisture to creep into the movement during a rainy commute or a hand-wash. By the time damage becomes visible, the repair bill is significant. Replacing the gasket proactively during every battery change eliminates that risk entirely.

Specification

• Sizes Included: 30mm, 31mm, 32mm, 33mm, 34mm, 35mm
• Quantity: 3 of each size
• Total – 18 Gaskets
• 0.6mm thickness

The process takes minutes. Open the case back, remove the worn gasket, clean the groove, and choose the closest matching size from the pack. Apply a thin film of silicone grease, seat the new gasket, close the case, and you are done. With 3 gaskets per size included, you have backups ready for the next service without reordering.

The O-Ring Gasket 0.6mm Standard Pack  is an excellent starting point for anyone building a watch repair toolkit for the first time. It covers the sizes you will encounter most often, at a price point that makes stocking up straightforward.

Measurement Guide

If you still have the old O-ring, even if it is stretched or broken, you can use it as a reference. Measure the Thickness, Use a digital caliper to measure the “cross-section” (thickness) of the rubber. Measure the Internal Diameter (ID): Lay the gasket flat on a surface without stretching it. Measure across the inside of the circle from one inner edge to the other.

If the watch is missing its O-ring entirely, you must measure the watch case itself to find the correct fit. Measure the Case Groove, locate the circular track (groove) where the gasket sits inside the watch case. Use a digital caliper to measure the Inside Diameter of that groove.

Order The O-Ring Gasket 0.6mm Standard Pack today and tackle the most common watch service job with confidence.