The Magpul MOE 9 Slot Polymer Rail is a picatinny rail section designed for use with MOE Hand Guards and Forends. The MOE Polymer Rail Section allows the attachment of various Picatinny rail-mounted accessories such as lights, vertical grips, etc. Made from an injection molded reinforced composite for enhanced strength, durability and lightweight. Size L4 (9 Slots), max overall length of 4.1". Made in the USA.