Callus Performance is used by worldwide athletes and fitness enthusiasts. The Callus Performance®'s patented solution is portable, safe, and easy to use. It rapidly removes calluses that can lead to injury and discomfort. Step up from pumice stones and razor blades to the next level. See results on your first use. Check out our online reviews, to hear it straight from other athletes. Callus Performance is built in the USA and designed by and for athletes. It's Made with a stainless steel blade, that can be used in any direction and hit those hard-to-reach spots on your hands. It also has a callus smoother one tip, so you can get complete end-to-end hand care in a minute.