A crimping method including providing a coupling including a sidewall and a ribbed stem having a plurality of radial valleys, the ribbed stem defining a longitudinal axis, wherein the first sidewall extends radially to the axis, and providing a die including a stop and a channel extending through the stop, the channel having a ribbed section with a plurality of ribs. The ribbed stem is inserted through the first stop, into the first channel and into the end of a hose. With a ferrule arranged between the ribbed section and the hose and the sidewall pressed against the stop, the die is used to compress the end of the hose between the ferrule and the ribbed stem with the plurality of radial valleys radially aligned with the plurality of ribs. The couplings are selected from a medical gas medical gas outlet rough-in and a medical gas nut nipple.