SQ 40.87 X 3.53

• NBR (Natural Rubber)
• Standard Service Temperature: -40°F - +250°F

Square rings are like O-rings however the cross-section is square instead of round. The square cross-section helps prevent rolling of the seal.

Polymers vary from 18% to 50% acrylonitrile content. Resistance to petroleum products increases as acrylonitrile increases; conversely, low temperature flexibility decreases.

Petroleum Fluids, Water (to 212°F), Silicon fluids, Ethylene Glycol, General Purpose

Nitrile compounds can exhibit excellent compression set, tear and abrasion resistance.

Not Compatible With: Phosphate esters, Ketones, Brake Fluids Strong acids, Ozone or weathering

The hardness of rubber compounds is measured by the Shore A durometer, the higher the durometer, the harder the compound. Softer compounds stretch easier and seal better on rough surfaces. Harder compounds offer greater abrasion resistance and resistance to extrusion.

• 60 Shore A is softer than 70
• 70 Shore A is the standard
• 90 Short A is very stiff