This is the Steyr Mannlicher M Model 4 round factory rotary magazine in 6.5x57 rifles with the new style dual side lock magazine.
The rotary magazine design is flush fit to the stock and is made of a tough polymer with a clear viewing plate at the rear.
Brand:Steyr
Weight:50 Grams
Calibre:6.5x57
Capacity:4
Model fit: M
Material:Polymer
Colour:Black
Item Nr.: 102-2400050505