The Sheltered Aisle ("Walk-in") is essentially an extension of the Electrical Equipment’s outdoor enclosure that can provide a weather resistant working area in front of and to the sides of the Switchgear. The electrical components form an integral part of the structure. Typically these are not climate controlled (other than filtered air), although many features can be added as needed. Since the Switchgear forms a part of the enclosure, a Sheltered Aisle (Walk-in) can be less expensive than a Power Distribution Center.