Description FEATURES–Designed to attach to existing shotgun magazine tubes to provide added capacity to the shotgun-Machined aluminum components combined with a lightweight carbon-fiber tube-Creates a lightweight, durable extension to your shotgun-An extra-long spring is included that can be cut to optimize loading-Extension clamps are recommended for extension tubes that extend beyond the end of the barrel-The LSX-3X adds three rounds to magazine’s capacity PRODUCT SPECIFICATIONS: Dimension     1.45 X 6.10 X 14.95 Height     1.4500 Width     6.1000 Length     14.9500 TYPE/COLOR     SHOTGUN MAGAZINE EXTENSION SIZE/FINISH     BENELLI M1/M2/SBE/SBE2 MATERIAL     CARBON FIBER/ALUMINUM OTHER FEATURES:     EXTRA LONG SPRING INCLUDED      THAT NEEDS CUT TO LENGTH,      PLUS 3 ROUNDS,      LENGTH 9.4″