Lee Westwood is the attached pro at Close House, where I'm a member. He swears by his Bioflow. So being even older than Lee & having a few aches & pains, I decided to try the same Sport Flex black model he uses. I would say that I noticed some relief after a few weeks. It's also pretty smart which is good with 21st century men wearing bracelets, necklaces, earrings and other adornments these days! It's comfortable & waterproof too. So those are clearly all positives. So why 4 stars rather than 5? Well, after a while, I got quite a skin reaction for some reason. So I had to remove it for a couple of weeks so that I could get better. I wear other stuff with rubberised straps like my fitness watch on a daily basis, and golf watch from time to time, but never had a reaction to those. A bit of a puzzle about the Bioflow.