Versatile sliding-shelf system increases storage space by 40-70% by eliminating unnecessary aisles; 4-shelf steel units move effortlessly on a track and lock when needed, allowing you easy, stable access to all sides of shelves; Kit includes everything you need for a 3-unit system with 48" x 24" shelves, including track; Ultra-flexible design is easy to set up and does not require track to be bolted to the floor, providing you with limitless setup options; Multiple unit quantities, shelf sizes, and weight capacity options available based on your storage space needs