Find the right O-ring in a few clicks
Start with the size you know. Then narrow by material, hardness and compliance. Every result is an APG stock part.
- 1Choose a size by dash number, inch size, metric size or your own measurements
- 2Pick a material, or answer a few questions about your fluids and temperatures
- 3Choose a hardness and open the part on callapg.com
Enter the dash number
Standard inch O-rings are numbered from -001 to -475 under the AS568 sizing standard. The number is usually printed on the old part's bag or drawing.
Choose the nominal inch size
Nominal sizes are the rounded fractions an O-ring is called by. For example, a 1/8 inch ring actually measures 0.139 inch thick.
Choose the metric size
Metric O-rings are sold by actual inside diameter and cross-section in millimeters.
Measure the old O-ring
Measure the inside diameter across the hole and the cross-section as the ring's thickness. We'll show the closest sizes we stock.
Match a material to your conditions
Choose everything the O-ring will touch, then the temperature range. Materials rated good or excellent for all of them are marked suitable.
What will the O-ring be exposed to?
Where will it be used?
Temperature range
How our materials compare
General guidance from published elastomer compatibility data. Concentration, pressure and exact temperature change results. For critical applications, confirm your choice with APG's technical team.
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