1/2" C x 1/4" C Copper Reducing Coupling,1/2" C x 1/4" C Copper Reducing Coupling, This copper coupling feature a rolled stop, which prevents the pipe from sliding past the center of the coupling, 1/2" x 1/4" Copper Coupling,Copper Couplings are used toconnect (2) copper pipes in a straight line.x 1/4" C Copper Reducing Coupling 1/2" C.