Whether you want to build dexterous, resilient fingers for hours of guitar wizardry, guitar hero wizardry or if you’re just looking to strangle a lot of people with your bare hands, the Planet Waves Varigrip Adjustable Hand Exerciser will get your digits in top form.

The Varigrip conditions your fingers, hand, wrist and forearm with adjustable tension and even simulated strings to keep your fingers in playing shape even when you’re away from your guitar. Set tension from light to hard individually for each finish, so if you’ve got weak pinkies, build them up to snuff.