This fitting is a 7/8" press x press copper coupling engineered specifically for refrigerant grade copper tubing. It uses RLS’s patented press technology to form two 360° metal to metal seals during installation, producing a permanent mechanical joint in seconds. Because it eliminates the need for open flame, nitrogen purging, brazing materials, and hot work permits, it significantly reduces installation time, labor cost, and jobsite risk. The coupling is part of the most widely used HVAC/R press fitting system, with more than 20 million fittings installed worldwide since 2015. It is fully UL-listed for high pressure refrigerants and approved for a broad range of modern refrigerants, including A2L blends.