These sturdy, deeper ATA amp racks incorporate dual rack rails (front and rear), heavy-duty casters, spring-loaded handles, and removable front and rear covers. Designed to protect and transport larger amps and other standard 20" Rack mount gear. Case includes four 3. 5" Swivel casters, 2 with brakes. (For more information about this product and other Odyssey products visit our website at www. Odyssey gear).