the one that fits on the reel , i,ve bought 2 new one,s this week and i still have to keep taking it off putting on at each house , i,ve tried the expensive and the cheap and no difference , until i take it off the water just trickles out of the brush , there is a pressure build up and you really have to tug it off the reel , when its replaced the water usually flows great , its very time consuming to keep doing it all day , any ideas what the problem is guys regards alan