And Google

Rich. I realise I should have titled this thread "What part do each of you use to stop your water systems emptying spontaneously?" as I can't imagine I'm the first to add a tap to their truck. I just need two little taps I can add to hoses for filtered water in gulping and at rear. The pictured one is for a beverage dispenser - I'm not sure how hardy they would be and are less suited to add to a hose [more for side wall mounting]. A lot of RV taps are massive and I'm having trouble finding one on boat/RV suppliers. I looked for Still but the name is a bit generic so couldn't identify it.
Edit - I think the correct term is hose union bib tap [i had no idea]
and these on RS are more like it.