Wilson Combat Extension Tube Left Hand 2 Shot 12 Gauge. Scattergun Technologies magazine tube extensions are so tough they were selected for use by the U.S. Secret Service and the U.S. Border Patrol. One Shot Magazine Extension Increases Magazine Capacity. Includes an Extra-Power Magazine Spring for Improved Reliability. Includes a High-Visibility Follower for Improved Feeding and Visual Reference of Empty Magazine Tube. Fits Remington M870 1100 1187 - 12 Gauge. Wave Washer Included. Only the strongest materials are used in constructing the magazine tube extensions to insure maximum resilience during rough usage. Each unit is shipped ready to install with our extra-power magazine spring and fully machined neon green high-visibility follower. Specifications for Wilson Combat Extension Tube for 12 Gauge Remington M870/1100/11-87: Manufacturer: Wilson Combat Color: Black Finish: Parkerized Gun Make: Remington Gun Model: Remington Model 11-87 Remington Model 1100 Gun Type: Shotgun Included Accessories: Extra-Power Magazine Spring Wave Washer High-Visibility Follower Condition: New Gauge: 12 Package Contents: Wilson Combat Extension Tube for 12 Gauge Remington M870/1100/11-87 What firearm models does the manufacturer say Wilson Combat Extension Tube for 12 Gauge Remington M870/1100/11-87 is compatible with? The manufacturer says that Wilson Combat Extension Tube for 12 Gauge Remington M870/1100/11-87 is compatible with Remington Model 1100 Remington Model 11-87Wilson Combat SGET-LH-2: Extension Tube Left Hand 2 Shot 12 Gauge