This product is either discontinued or we cannot get that from suppliers.
Advanced Rails For Intel Server Chassis P4000 AXX3U5UPRAIL, Metal, Metallic, Compatible P4000M/P4000L/P4000L-WS Server Chassis.
The Intel AXX3U5UPRAIL is an Advanced Rail Kit for P4000M/P4000L/P4000L-WS Server Chassis used when converting Pedestal chassis to 4U rack chassis, and full extension rails are needed.