This replacement Bone and Skin Insert for the Basic Intraosseous Trainer allows you to replace just the used portion of the Basic Intraosseous Trainer. The trainer has a soft skin with thickness of 7mm, a cortical bone with thickness of 2.5mm, and marrow with thickness of 23mm. The realistic feel of skin and bone materials allow for amazing realism right up to the “drop” in resistance felt when advancing past the cortical bone. The low price point makes it possible to purchase multiple trainers for a larger class and allows for each trainee to practice many times. With proper use, you can get 100+ accesses in each model.