Brought one of these to evaluate the it as part of a series of upgrades for the club boats. The retaining screw fell out and rooster where not able to help. Fortunately Ronstan did and provided a replacement free of charge. Have also evaluated the Rwo equivalent and have used this for the rest of the boats for 3 reasons - it use a pin to attached to the mast so should stay on, it is shorter (getting on to 20mm) which means there a little more adjustment in the kicker and finally they are a few pounds cheaper (which helps when you are upgrading a number of boats)