ADD 4 INCHES TO FRONT OR BACK RACK MOUNT: Rail-depth adapter kit lets you mount rack equipment so that it either extends four inches (10.2 centimeters) past the front vertical mounting rails or recesses four inches within the rails. STANDARD RACK COMPATIBLE: Compatible with EIA-standard 19 inch open frame racks and enclosures EASY TO USE: 1U brackets come with all necessary mounting hardware for easy installation. Position the brackets outside the rails to increase rack depth or inside the rails to decrease rack depth. HEAVY-DUTY CONSTRUCTION: Made from heavy-duty steel with a black powder-coated finish to match your rack. RELIABLE PRODUCT FULLY BACKED AND SUPPORTED: This product is covered by a 5-year limited manufacturer's warranty and is supported by Tripp Lite's Chicago-based expert technical support team over phone and email.