The deep design is ideal for most PA/DJ equipment, such as amplifiers, effects, cables, etc. These 6-unit rack cases are made of lightweight ABS with aluminum rails and trim, as well as reinforced handles, designed for transporting your equipment. These racks offer excellent protection for your equipment during transport. The shallow design is great for smaller equipment such as wireless microphones, preamps, etc. These 6U racks are 21 centimeters deep and feature standard 19-inch mounting rails; spring-loaded handles, sturdy butterfly latches, and rack screws are included!