Product Information Seal: Buna-N Select a Product Part NumberMaterialSize 200-TCA-AL356T6 Aluminum2" 300-TCA-BRBrass3" 300-TCA-AL356T6 Aluminum3" 300-TCA-SS316 Stainless Steel3" 200-TCA-SS316 Stainless Steel2" 400-TCA-BRBrass4" 400-TCA-AL356T6 Aluminum4" 400-TCA-SS316 Stainless Steel4" 300-TCA-MIIron3"