A reference standard device intended to represent one end of a medical quick-connect coupling or a terminal unit of a gas-specific format [e.g., oxygen (O2), nitrous oxide (N2O), medical air], which may be used to evaluate connection port compatibility and integrity. It is designed with specific gas and device type mechanical mating patterns whereby it may also be used to test the medical gas pipeline integrity (i.e., test for leakage). It may consist of both a male end (to test a female socket) and female end (to test a male plug). This device is intended to be used by a professional in a professional setting (e.g., clinical engineering).