This 20 round body detachable polymer magazine utilizes a steel floorplate for strength and features ergonomic finger groove grips on the magazine body. It is designed primarily for composite stocks, but can be used in rifles with wooden stocks after some minor modifications to the magazine opening. Only insert/remove this magazine with the bolt locked in the rear position. 

Notes:

Will not fit in the Russian SKS without modification

Can be used in factory wooden stocks by filing the inside of the magazine well on the wooden stock, in order to accommodate the wider polymer magazine.