Wheeler Front Sight Tool, For AR Rifles, Black 156437 The Wheeler Delta Series AR Front Sight Tool is a 4-prong front sight tool designed to install and adjust the A2 front sight found on the AR-15" M16" and M4. It is machined from steel and has a black zinc finish to last for years. The key ring serves as a handle and helps keep the small tool accounted for. Can be used with any 1/4" hex driver.