BrassCraft 1/4-in x 1/4-in Threaded Female Adapter Coupling Fitting in the Brass Fittings department at Lowes.com
1/2 in. Size Zinc Plated Two Lug Female Threaded Coupling (NPT Threads)
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