ERGO 15-Slot 6in .400 Ultra Lite Aluminum UMP M1913 Picatinny Rail Black. These Picatinny Rails manufactured by the experts at ERGO are made of aluminum and include mounting hardware. Specifications for ERGO 10-Slot 4in.400 Ultra Lite Aluminum UMP M1913 Picatinny Rail w/ Ergo Rail Cover: Manufacturer: ERGO Color: Black Fabric/Material: Aluminum Gun Rail: Picatinny Gun Type: Rifle Gun Make: AR Platform Condition: New Features of ERGO 10-Slot 4in.400 Ultra Lite Aluminum UMP M1913 Picatinny Rail w/ Ergo Rail Cover Mounting does not require alteration of AR Handguard heat shields Package Contents: ERGO 10-Slot 4in.400 Ultra Lite Aluminum UMP M1913 Picatinny Rail w/ Ergo Rail Cover ERGO 4762: 15-Slot 6in .400 Ultra Lite Aluminum UMP M1913 Picatinny Rail Black