Action Army AAP-01 Gas Drum Magazine pistol light High capacity (Hicap) magazines usually

High capacity (Hicap) magazines usually hold 150 rounds or more

fully metal

but we are not sure

 Piston Teeth: 14 MIM Steel Piston Teeth

Light-weight Aluminum Bottle (flat bottom cylinder)

Action Army AAP-01 Gas Drum Magazine pistol light High capacity (Hicap) magazines usuallyThe AAP 01 Drum Magazine from Action Army gives you nearly bottomless fun on the airsoft field. This gas drum magazine holds 350 BBs, and is filled using the extra large easy fill cover. Instead of a winding wheel, this magazine uses a flash mag pull string for ease of loading. A QD sling socket on the back allows you to attach a sling to protect your magazine from being accidently dropped. The AAP 01 Drum Magazine is compatible with all TM spec