BUD Industries TBC-14263 Aluminum Ventilated Top or Bottom Cover, 21-7/8" Length x 16-25/32" Width x 27/64" Height, Natural Finish, for Rackmount Chassis Ventilated top or bottom cover: 0.05" aluminum, natural finish, 0.12" by 0.75" slots for maximum ventilation Rear mounting brackets Front panel: 0.12" thick mill finish aluminum with "surface shield" protection Handles: chrome plated steel, 2 required Measures 21-7/8" length by 16-25/32" width by 27/64" height