This fittings are the first carbon steel press system for gas applications and can be used with schedule 5 to schedule 40 black iron pipe. These fittings reduce installation time by eliminating the need for messy cutting oils, heavy threading equipment, and fire watches. The patented smart connect technology allows installers to easily identify unpressed connections during pressure testing. Suitable for use with natural gas, liquid propane gas, diesel fuel, and compressed air, these fittings provide a secure, flameless connection in seconds.