XSPC 1/2" x 3/4" Compression Fitting with G1/4" Threads (Chrome Finish) Chrome Finish For Tubing with 1/2" ID (Inner Diameter) and 3/4" OD (Outer Diameter) G1/4" Threads with black o-ring for leak-proof seal Easy tool free coin installation (coin fits into notch on the barb) Low Profile Design