Parker Butyl Rubber (IIR) O-Rings

Parker Butyl (IIR), Isoprene® O-Rings Material Description:

Parker Butyl (isobutylene, isoprene rubber, IIR) o-rings have a very low permeability rate and good electrical properties.

Parker O-Ring Distributor

For over 50 years, Engineered Seal Products has partnered with Parker Seals. ESP is proud to be one of the FEW Premier Distributors to qualify as a "Parker Seal Technology Center (STC)".

What does Parker STC mean?

  • Proven Engineering Capability
  • Expert Material & Technical Support
  • ISO Quality Approval
  • Strong Financial Track Record
Parker Butyl (IIR), Isoprene Chemical Resistance:
  • Hot water and steam up to 121°C (250°F)
  • Brake fluids with glycol base
  • Many acids
  • Salt solutions
  • Polar solvents, (e.g. alcohols, ketones and esters)
  • Silicone oil and grease
  • Ozone, aging and weather resistant
Parker Butyl (IIR), Isoprene Not Compatible With:
  • Mineral oil and grease
  • Fuels
  • Chlorinated hydrocarbons

Parker Butyl (IIR), Isoprene O-Rings Compound Numbering System:

Parker has one type of nomenclature used to reference Butyl (IIR), Isoprene® products.

Polymer Code (Single Letter)
Sequence Number (Four Digits)
Durometer Indicator (Two Digits)

Parker Butyl (IIR), Isoprene® O-Rings Compounds:

Parker Compound Number Datasheet Hardness (Shore A) Low Temp High Temp Color Recommended For
B0318-70 PDF 70 +- 5 -75°F 250°F Black General Purpose.
B0612-70 PDF 70 +- 5 -75°F 250°F Black Vacuum, Low Compression Set.

ASTM Designation
Shelf Life
15 Years
Hardness (Shore A) Range
30 - 90

Temperature ranges will apply to the majority of media for which the material is potentially recommended. With some media however, the service temperature range may be significantly different. ALWAYS TEST UNDER ACUTAL SERVICE CONDITIONS.

ESP’s shelf life recommendation is based on the ARP 5316 standard and intended to be utilized by those organizations who do not already have specific recommendations for the control of elastomeric seals. It should be noted that the packaging of the elastomeric seals prior to assembly into a product is an integral part of the controlled storage procedure. It provides a positive means of product identity from the time of manufacture, to the time of assembly.