CP Aerial Check Valves are built for the demands of aerial application. The patented needle/seat design provides instant shut-off, with a stainless needle seating into an O-ring in a stainless core. A Viton diaphragm protected by a Teflon diaphragm on the needle ensures long-lasting, reliable performance. Choose stainless steel for maximum durability or glass-filled polypropylene for a lightweight, cost-effective option.