No longer will the lack of quality magazines keep shooters from taking advantage of pistol caliber AR-15s. These polymer magazines fit perfectly into the magazine well on any standard AR-15 lower receiver without the need for receiver blocks. Alleviating a common problem with pistol caliber AR-15's which is the need to alter pistol caliber magazines to fit and function in an AR-15. These magazines will provide reliable function in your AR-15. Available for the 40 S&W, 10mm, and the 45 ACP; these magazines will hold 17 rounds of 45 ACP and 10mm and the 40 S&W will hold 20.