O-Ring Gauge Make Work Smart, Telescoping O Ring Sizing Plastic Gauge, Slide Style National Type, for Measuring O Rings Inner Diameter, OD, Thickness Gauge Blue

Measures o rings nicely just don't stretch the o ring to far or you will get a misreading.

This o-ring gauge is made of heavy plastic, slides freely, marks for o-ring size are printed in white against blue and therefore easy to read. Smaller o-rings can be sized against accurate printed silhouettes on each side of the gauge. All sizes are shown in common "-dash" numbers for easy reference at the local bearing or tubing store. There are slots at the top of the gauge to "size" the o-ring's cross section. Instructions for use are clearing printed on one side so they're never lost and are easy to understand. Overall gauge length is 13.5 inches by 1.25 inches square. As with any extendable gauge, the tension you apply is key to accurate measuring. If this is to be kept loose in a tool box, I'd recommend you retain its cardboard box or have a friend sew a sleeve. This will protect the printing from becoming scratched or grease from making the markings unreadable.

Works great as it should

The gauge read two sizes smaller. The size for a 025 o' ring is shown on the chart as ID 29.87 mm . The vernier caliper measured ID as 33 mm which is for a 027 o' ring. O well, I guess I will have to estimate it up or I might consider returning the tool

Now i can have assurance I am reading the correct size. This tool will save me a load of angst!

Herramienta de Trabajo

Can't recommend this tool highly enough. It is a must have if you work with O-rings