SKB's 30 inch 3RR Series Removable Shock Rack Transport cases are now available in 3 sizes, 3U, 4U, and 5U. These Shock Racks are lightweight, shockproof, watertight, dustproof, heat and chemical resistant, perfect for protecting and transporting your sensitive electronic equipment. Molded of LMDP Linear Medium Density Polyethylene plastic that meets or exceed MIL-STD 810G standards and includes 8 elastomeric shock absorbers which allows a standard payload range of 40 to 150 pounds. Optional extended payload range of 160 to 300 pounds can be accommodated as a special order option. These 3RR Series Removable Racks are 30 inch deep from rail to rail with a standard 19 rack width per ANSI/EIA-310-C specification and feature square-hole rack rails to accommodate either 10-32 US standard, or 6mm International standard cage nuts which are supplied with the cases. The rugged roto-molded shell ensures industry leading strength and impact resistance. The standard COTS (commercial off the shelf) case comes with a 2 inch deep front lid and a 5 inch deep rear lid to accommodate rack gear that is longer than 30 inches, and edge casters to allow convenient case transport. Molded-in stacking ribs and lugs are designed to stack with competitive manufacturers cases. Black powder coated stainless steel hardware are recessed for protection is standard as well as 8 comfort grip spring loaded lift handles which allow for easy movement. An automatic pressure relief valve is another standard feature along with gasket sealed lids that include convenient lid hangers to store your lids when your equipment is in operation. Coupling straps are included for securing the racks together when stacked. The interior rack chassis slides out and is fully removable from the inner rack frame. This feature allows the user to remove the chassis from the case for integration and maintenance of equipment to allow full access and convenience on a workbench. The inner chassis is held in place with our patent pending "positive lock" securing system that consists of two (2) die cast latches on the front end of the frame and chassis. The "positive lock" securing system ensures that all shock and vibration is transmitted directly to the elastomeric isolators to allow efficient reduction of harmful conditions.