Aim straight - thanks -the ten rings site has some really useful reading, not just about grips.

Mike - mine says M.

Big Ears - I have tried a more relaxed grip and it's much better but I think the muscle pad below my thumb is pushed up by the grip, forcing the inside of my thumb nuckle into the underside of the top grip. Yesterday left marks, but today it hasn't.

I will ill persevere for a bit longer until the grip feels more natural -I've never had such an anatomical grip. I m guessing my dilemma will be if I get a Large grip or cut some away from this one.

Next question-the cylinder I fitted needs swapping and I'm struggling to unscrew it , is there something to do to release pressure ? Or have I just got weak hands?