MEC Stainless Steel braided pigtails are for connecting propane cylinders to the propane regulator. The Stainless Steel braid provides added protection to the hose along with the safety features of thermal protection in case of fire and excess flow protection in case of broken gas line. Female QCC, Type I connection x 1/4' inverted male flare. MEC green Type I Nut for use on RV application ONLY. (200, 000 BTUH)