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Pi Tape® brand Precision O-Ring Inside Diameter tapes are specifically designed to achieve quick, accurate inside diameter measurements of O-Rings and other soft-walled parts.

Tapes with a starting point of 2” (50.8mm) are made with a 1/4" (6.35mm) wide Gage Member and a 1/2" (12.7mm) wide Vernier Section. The standard thickness for 1/4" X 1/2" (6.35mm X 12.7mm) in Spring Steel, Blue Or White Easy to Read is .005" (0.13mm) and for Stainless Steel is .006” (0.15mm).

Tapes with a starting point of 12” (300mm) are made with a 3/8” (9.53mm) wide Gage Member and a 3/4" (19.05mm) wide Vernier Section. The standard thickness for 3/8” X 3/4" (9.53mm X 19.05mm) all material is .010” (0.25mm).

  • Standard O-Ring tapes have an accuracy of ± .003” up to 48” (± .09mm up to 1200mm)
  • Standard O-Ring tapes starting between 48” -72” (1200mm-1800mm) and extended range tapes (tapes with over 12”/300mm of usable range) have an accuracy of ± .005” up to 72” (± 14mm up to 1800mm)
Each Pi Tape® brand precision measuring tape is furnished with a Calibration Report whose measurement results are traceable through NIST to the international system of units (SI).

Please click here to view our ISO/IEC 17025:2017 Certificate of Accreditation (pdf). Not all items we calibrate are included in our scope, however the calibration techniques and procedures are all in compliance with ISO/IEC 17025:2017.

Specialty sizes, widths and larger tapes are available upon request.

 O-Ring Inside Diameter Price List

 Custom Made O-Ring Inside Diameter Price List