Midland Metal 20056 Straight Connector, 1/4 in Tube OD x 3/8 in Male NPTF, Brass

Male Adapter, Connection Size 1: 1/4 in, Connection Type 1: Push-to-Connect, Connection Size 2: 3/8 in, Connection Type 2: Male NPTF, Brass, 1/4-18 x 3/8-18 Thread, 0.68 in Hex, 0.94 in L, -10 to 200 deg F