Smith Cooper 150# Black Malleable Iron 1/2 in. Banded Coupling Pipe Fittings - Threaded - John M. Ellsworth Co. Inc.
Horiznext npt 1/2 (means the inner diameter of the thread is 3/4 inch) cast female taper threaded pipe coupling, stainless steel 304 coupler for mush tun cooler and shower hose, 2 pcs - Amazon.com
1-1/2 in Merchant Steel Coupling, Sch. 40 Galvanized Pipe Fitting, Class 150 - GP130112 - Hi-Line Inc.
1 1/2 in. Galvanized Iron Compression Coupling — PIPE DECOR