The Milwaukee Vertical E-Track is for use with PACKOUT Racking Shelves and features a powder-coated finish to resist rust and corrosion. Its heavy-duty steel construction is ideal for mounting in vans, trucks, trailers, and shops and is compatible with all E-track accessories. Each E-Track has five slots for versatility. The PACKOUT Modular Storage System is the industry's most durable and versatile storage system. (5) E-Track mounting slots per piece. Includes two pieces of E-Track, 3-1/2 In. W x 20 In. L.