Gator Cases GR-RACKBAG-4U 4U Lightweight Rack Bag is great for effects processors, recording and audio equipment, and sound modules. Constructed of 600 Denier nylon exterior with polyethylene reinforced interior frame and internal reinforce aluminum valance. An ergo grip carry handle makes for easy transportation. It's rear flap allows for access to entire panel of equipment and exterior pocket for cables make this the ultimate 4U rack bag.