Features Automatically winds with the sound from your gun firing! Onboard switch can also be used for manually triggered electric winding Solid and durable steel shell drum magazine Realistic feel, look and size Realistic single-drum design Wind with the simple press of a switch Uses 3 AA batteries (sold separately) Manufacturer: Matrix (CYMA) Specifications: Compatibility: Tokyo Marui, CYMA, JG, Echo 1, G&P, Matrix, and other compatible AK Series Airsoft AEGs Capacity: ~2500 rds Material: Steel / ABS Winding: Push button or sound activation