Steel rack rail square holes is the ideal choice for most applications that require 3/8″ square hole rail. Retrofits easily into most rack cabinets, rack enclosures or rack case applications. Our rack rail square holes are flat black powder coated and conveniently etched every 1-3/4″ for ease of component mounting. Made of 2.5mm thickness steel with 3/8″ square holes on one side for equipment mounting and .276″ diameter holes on the other side used for mounting into a cabinet, case, or custom enclosure. Sold in pairs and available in lengths from 2U to 45U. Ships fast, within 1-2 business days for most orders, depending on the time of day the order is placed.