Wilson Combat Spring and Follower Kit Extension Tube 12 Gauge. Extra-Power Magazine Spring for Improved ReliabilityHigh-Visibility Follower for Improved Feeding and Visual Reference of Empty Magazine TubeFor Use with 2 Shot Extension Tube or Remington 3 Shot Extension Tube Fits Remington M870 ; 1100 ; 1187 - 12 Gauge; Specifications for Wilson Combat Spring and Follower Kit Extension Tube: Manufacturer: Wilson Combat Color: Silver Magazine Capacity: 2 Round Package Contents: Wilson Combat Spring and Follower Kit Extension Tube Wilson Combat SGSFK-EX: Spring and Follower Kit Extension Tube 12 Gauge