The Tantus Fist Trainer mimics the natural shape of a closed hand and is the perfect way to prepare for or simulate fisting. The ribbed shaft adds pressure and releases crazy brain chemicals when removed. Made of 100% Ultra-Premium Soft silicone, this is an advanced toy for people who know what they are doing and demand quality from products they put in their bodies. Harness Compatible: Yes Safe For Your Body: Made from Tantus’ own unique formula of 100% Ultra-Premium Silicone Easy To Clean: Eco-Friendly, Hypoallergenic, Hygienic, Boilable, Bleachable and Dishwasher Safe. Shaft Diameter: 2" Max Head Diameter: 2.8" Length: 10" Weight: 1lb 5oz