O-Rings

There are several different standards to choose from when it comes to O-ring dimensions.  The most popular in the United States is the AS568 standard for O-ring sizes and tolerances.  Maintained by the Society of Automotive Engineers, this standard allows the user to choose from five different cross-sections with inside diameters ranging from 1/32" to 26". Tube fitting boss seals are included in AS568 as 900 series O-ring sizes, and are intended for use in MS33649 (now superseded by SAE-AS5202) straight thread tube fitings. 

RT/Dygert also offers a wide array of metric sizes, in both standard and non-standard dimensions.  As a subset of the metric sizes offered, we also stock many Japanese Industrial Standard (JIS B2401) sizes. If an O-ring with special size or fluid resistance is required, RT/Dygert can provide custom O-rings, specially made to your demanding requirements.