At my Mom's house we used these outdoor water spigots (2) (hot and cold)
http://www.homedepot.com/p/Prier-Pro...9-14/204679415
Then we cut a hose in half and mark Hot and Cold at both ends. It makes installing and breaking down the system so much easier. No repairing burst pipes come spring time.
Take the shower/tub assembly and mount it to a piece of composite decking. At the end of the season take it off the wall of the shower and store it in the basement if heated, so the assembly won't freeze. Coil up the hoses and store with the shower assembly. I recommend the Tub port for filling up hot water buckets, it really comes in handy.
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