19" Server Rails(2) Pair of full height 19" EIA mounting rails, accepts cage nuts, U markings on front and rear of each rail.Depth markings included on frame for easy alignment.Accessory mounting holes along rails allow for mounting of cable management fingers and tool-less accessories.Rectangular cutouts for routing cables through 800mm (31.5") wide 19" EIA rails from front to rear or for airflow for side breathing equipment.48U x 800mm Wide 19" Server Rails Square Hole Black (Qty 2)