MEC™ Excela-Flo™ Stainless Steel Braided Pigtail (MER425SS-24P) by Marshall Excelsior. Length: 24". Standard QCC with Braided SS Hose. 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.