Add five extra feet of storage to your existing Lifetime 11 Foot Outdoor Storage Shed with the Lifetime 11 x 5 Foot Outdoor Storage Shed Expansion Kit with Two Windows from Lifetime Sheds. You ll not only get an extra 5 feet of storage space but also two shatterproof windows for twice the air circulation and twice the natural light. This expansion kit is constructed from high-density polyethylene (HDPE) plastic with powder-coated steel reinforcements and it s weather- and- rust-resistant and designed to withstand even the harshest elements. And since this shed expansion kit is UV-protected and stain-resistant it requires no painting sanding or staining.