I am considering buying a Stuart Turner power shower pump. As I am living in Southern Ireland our copper pipe sizes differ from the UK which is where the pump is made. The difference between the pipe is the UK pipe is 22mm outside dia. and the Irish pipe is 21mm outside dia. When you purchase the pump you are given the choice between 22mm olives or 21mm olives to suit both size pipes. My query is this, when looking at the nut and ring for the 21mm pipe, the collar on the nut does not close off the ring. i.e. you can see the edge of the ring coming through the nut. Will the joint seal when assembled and tightened?