Features Polymer construction High tension spring ensures reliable feeding 20 round capacity Factory spare magazine Color: Translucent grey Compatibility: ASG M40A3 series spring Airsoft rifles Capacity: 20 Rounds Materials: Injection molded polymerAbout the ASG M40A3 Sportline 27-round magazine This is a spare magazine for the ASG M40A3 sportline sniper rifle. This will **NOT** work on any other M40 type guns from ASG. To use this magazine you must have a BB loader to load it. We recommend .25g BBs or heavier for sniper rifle class airsoft guns. Here is a tip if you are playing with a sniper rifle: If you are running around in a game as a dedicated airsoft sniper be sure to get a lot of these as you will be running out of ammo frequently, or explore getting a pistol as a backup to use for closer range. These magazines are very light and you can carry a lot of them for a lot less cost than a gas gun magazine though, so you might considering biasing your budget towards these magazines.