Amazon.com: FangKingNo 10pcs 1/2 Inch White 2-Way PVC Male Adapter Pipe Fittings (Socket x Male Pipe Thread) Coupling with 1/2-Inch Male Thread Schedule 40 -10 Pack (0.5 Inch) : Industrial & Scientific
316 Stainless Steel, 1/2 in x 1/2 in Fitting Pipe Size, Coupling - 6JM28|60FC111N012 - Grainger
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
Amazon.com: FangKingNo 10PCS 1/2" to 3/4" PVC Reducing Nipple Male Thread to Male Thread Coupling for PVC PIPE Pressure Fittings,PVC Male Adapter for PVC PIPE Connector White (1/2 Inch to 3/4 Inch) :
Black Pipe Fittings - 1-1/2 NPT Right & Left Coupling, 150# UL/FM
Sigma ProConnex 1/2-in Zinc-plated Steel Threaded Coupling Conduit Fittings in the Conduit Fittings department at Lowes.com