The Pro Impakt D3O J has been specially developed for young athletes looking for the best protection on their outdoor adventures. The intelligent D3O material is flexible and offers full freedom of movement, but locks instantly on impact to absorb and disperse the energy, significantly reducing the risk of injury.Equipped with an adjustable waist belt and chest strap, this back protector adapts perfectly to the young rider's body and ensures a stable fit even in the most intense conditions. Enjoy every descent safe in the knowledge that your back protector will stay in place.comfort is key on long days on the piste or on the trail. The Pro Impakt D3O J back protector is made from breathable and ergonomic materials that mould to the contours of your back. A perfect fit and high-quality materials ensure exceptional comfort. The back protector stays in place without restricting your child's freedom of movement, so they can concentrate on the essentials - for an unrivalled mountain biking or skiing experience.