Made of Buna-nitrile (also called Buna-N) for use with a variety of fluids and hydrocarbons Temperature Range: -35°C (-31°F) to 120°C (248°F); Shelf-life: 15 Years These versatile o-rings perform well in petroleum based oils & fuels, aliphatic hydrocarbons, vegetable oils, silicone oils & greases, ethylene glycol, dilute acids, and water to below 100°C (212°F) Durometer (hardness) of 70A for resistance to penetration O-ring Size meets standards defined by AS568A (b) ID (Nominal): 6-1/2 ID (Nominal): 1/4 CS (Nominal): 7 OD