Hi Noob, I purchased the Mosmatic boom elbows directly from
Kleen-Rite (Part #: BOMP60314). They don't swivel. You'll need to call them for current prices. 1-800-233-3873. Their elbows come with a heavy duty hose clamp, but we still welded the elbow to the Mosmastic 3' extension (Part #BOMP60315). I definitely recommend adding the 3' boom extension! Though it does add weight to the Diskin wall bracket, it takes the pressure off the hose so customers aren't pulling the hose to get it over their cars. As for the weight, we ended up adding brackets, with long screws and drilling them through the thick concrete walls.