Choate Tool Winchester SX2 SX3 SX4 Browning Gold and Browning Silver 7 Shot Magazine Extension 12 Gauge. These extensions are great for law enforcement officers competition shooters and home protection. Will not fit SX1 shotguns. These kits are constructed of solid blued steel and come with spring base clamp & follower. 7 Shot Model fits 18? barrel or longer. 8 Shot Model fits 20? barrel or longer. 9 Shot Model fits 24? barrel or longer. 10 Shot Model fits 26? barrel or longer. Specifications for Choate Tool Winchester SX2 SX3 SX4 Browning Gold and Browning Silver Magazine Extension: Manufacturer: Choate Tool Gun Make: Winchester Browning Gun Model: Winchester SX2 Browning Silver Winchester Super X3 Winchester Super X4 Browning Gold Condition: New Country of Origin: USA Features of Choate Tool Winchester SX2 SX3 SX4 Browning Gold and Browning Silver Magazine Extension Adds +2 shotshells machined from steel includes spring follower and clamp Package Contents: Choate Tool Winchester SX2 SX3 SX4 Browning Gold and Browning Silver Magazine Extension What firearm models does the manufacturer say Choate Tool Winchester SX2 SX3 SX4 Browning Gold and Browning Silver Magazine Extension is compatible with? The manufacturer suggests that Choate Tool Winchester SX2 SX3 SX4 Browning Gold and Browning Silver Magazine Extension is compatible with Browning Gold Winchester Super X4 Winchester Super X3 Browning Silver Winchester SX2Choate Tool CMT-03-04-22: Winchester SX2 SX3 SX4 Browning Gold and Browning Silver 7 Shot Magazine Extension 12 Gauge