Two Shot Magazine Extension Increases Magazine Capacity to 6 Rounds; Sling Mount for Right Hand Shooter, Mounts on Left Side; 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; Black Finish