Ingersoll Rand's MS Series Industrial Interchange Couplers & Plugs are automatic type, one-way shutoff couplers. ; Pair with any Ingersoll Rand Industrial Style or Universal Style coupler. This connector kit is industrial type, 3/8" size, and includes a 1/4" female coupler, 1/4" male plug, 1/4" male coupling, and 1/4" female coupling.