Hollis has become a leader in the sidemount market. It is not just a fad and not just a tool for cavers, it’s here to stay and is growing. The Hollis SMS 75 Sidemount System is an evolution from years of sidemount development, which started with the Hollis SMS 100. A product that has been copied, modified and a benchmark for technical sidemount for years. Even more popular has been the lightweight Hollis SMS 50 line. These two have taken sidemount mainstream and the building blocks this new harness.