382-piece Kit contains the 30 most popular (SAE) Square O-Ring sizes - see images for chart. Square O-Rings for static applications where high sealing load force is required Temperature range -65 deg F to +250 deg F 70 Durometer Buna-N Square O-Rings packed in a convenient plastic case For use with water, gasoline, hydraulics and pneumatics

Master kit contains virtually every common size Standard-SAE Square O-Ring you might require. Commercial quality black Buna-N / Nitrile rubber, a copolymer of Butadiene and Acrylonitirle. Resistant to mineral oil-based lubricants and greases, many grades of hydraulic fluids, aliphatic hydrocarbons, silicone oils and greases and water.