The MSR Zone MTB Knee Guards were designed with comfort, mobility, and breathability in mind. We wanted a knee guard that maximized protection while minimizing bulk. That's why we partnered with D3O to create one of the most comfortable knee protections out there. The Zone Knee guard features a CE rated LP1 D30 knee pad and is constructed with lightweight and breathable 4-way stretch materials, and an anti-slip silicone thigh band for all day comfort.