Magpul Industries ESK Safety Selector Polymer/Steel Ambi 60/90 Degree Opti FDE. The ESK AR includes three levers: full short and hybrid a selector pin and a reversible corrosion-resistant steel selector axle with 60 and 90-degree options. The selector pin comes in either black or red and secures the lever to the axle while acting as a selector position indicator. Installing the levers is easy and can be done without any tools. When its time to remove a lever all thats required is a punch. With smart design and ergonomic angles in the right spots this kit allows multiple selector variations and easier firing hand selector manipulation to allow a modern manual of arms to be employed. Designed for Mil-Spec AR-pattern lower receivers. Not compatible with select fire receivers Specifications for Magpul Industries ESK Safety Selector: Manufacturer: Magpul Industries Gun Type: Rifle Gun Model: Knight's Armament M110 SR-25 AR-10 M16 M4 AR-15 Fabric/Material: Polymer Hand: Ambidextrous Features of Magpul Industries ESK Safety Selector THREE USER-CONFIGURABLE LEVERS FOR AMBIDEXTROUS USE Reversible steel axle allows for 60 or 90-degree selector throw CONSTRUCTED OF HIGH-STRENGTH POLYMER AND CORROSION-RESISTANT STEEL Easy drop-in installation Package Content of Magpul Industries ESK Safety Selector What firearm models does the manufacturer say Magpul Industries ESK Safety Selector is compatible with? The manufacturer says that Magpul Industries ESK Safety Selector is compatible with AR-15 M4 M16 AR-10 SR-25 Knight's Armament M110Magpul Industries MAG1254-FDE: ESK Safety Selector Polymer/Steel Ambi 60/90 Degree Opti FDE