Scandvik 10003 Chrome Plated Brass Compact Bulkhead Connection For Shower Hose, 3/8" BSP-M Hose Connection" 

Chrome plated brass mixer with compact trim ring. Ceramic valves for a drip free faucet. 1-3/4" Mounting hole. 1/2" NPT female straight connection with 1/2" hose barb fittings included. If you are using a shower rail, the chrome/brass bulkhead elbow may be required to route the plumbing behind the bulkhead for a clean installation.