This product does what it's supposed to do, it checks the stiffness of the tires before it rolls my 18 wheeler onto the road. What I don't like is that it's not heavy enough at the end of the shot and the grip needs better grip. The need for a better grip is NOT the manufacturer's fault, it's the LAW that says that when you pick up that TOOL, it becomes a WEAPON! The knife is also a tool and can be used as a weapon, but I'm not going to check tires with it!