These Savers pens are worth their weight in gold. I build and work with them pretty hard and have had to replace more grips for as long as I can remember. Now I have them on all ax handles and sledgehammers and I have never broken them since. Using an ax or sledgehammer regularly will definitely save you time and money. There's nothing worse than halfway through a job or project when your tools break and you have to start a new pen or get a new tool. Installation is easy, it takes some effort, but it fits very snugly, which is good because you don't have to worry about it moving towards you. I definitely recommend it.