Choate Tool 9&10 Shot Magazine Extension Spring 12 Ga. WILL NOT WORK ON MOSSBERG 930 LOOK AT PART #60-09-17 Specifications for Choate Tool 9&10 Shot Magazine Extension Spring for 12 Ga.: Manufacturer: Choate Tool Condition: New Country of Origin: USA Magazine Capacity: 10 Round Caliber: 12 Gauge Features of Choate Tool 9&10 Shot Magazine Extension Spring for 12 Ga. 9 &10 Shot Magazine Extension Spring For 12 GA. Package Contents: Choate Tool 9&10 Shot Magazine Extension Spring for 12 Ga. Choate Tool CMT-60-09-12: 9&10 Shot Magazine Extension Spring 12 Ga