[volksworld]

the lowes one you show is set up for pex so the barbs are different from normal ones but will probably seal just fine...the marine one is good cause it has a mounting tab but 3/8 pipe thread is overkill and makes it unnecessarily bulky....the tractor supply one looks like a plastic p.o.s. for a lawnmower...a 1/4 inch ball valve rated for propane from a plumbing supply house is all you need(with two 1/4 pipe x 5/16 barbed fittings and some Teflon tape)