This magazine is made of metal and fully compatible with aftermarket airsoft guns taking AK magazine. The capacity of this magazine is 500rds and the internal compoments of the magazine are imported from Japan. Extremely smooth loading of the BB means no re-wind is necessary after one full wind up. 

A.P.S. 500rd Type 74 Cal 5.54 Metal Hi-Cap Magazine for ASK/AK AEG 
Steel housing Magazine 
Suitable for ASK/ AK Series Airsoft Electric Gun AEG Rifle 
500 Rounds Loading Capacity 
Realistic Texture 
Large thumb dial on bottom of magazine allow you to wind up the compression spring 
SKU    APSH-MAG-AEK037
Item Weight (gram)    230
Major Color    Black
Loading Capacity    500 Rounds
Magazine suitable for    ASK/ AK Series Airsoft Electric Gun AEG Rifle
Magazine Type    Standard
Bullet Type    6mm BB
Manufacturer    Accuracy Pneumatics Shooting