Lancer shotgun extension clamp picatinny rail both sides FEATURES-Shotgun Extension Clamp for use with the LSX Shotgun Extension Tube-The two aluminum clamping halves have high temperature silicone foam pads to ensure a slip free connection with the carbon-fiber tube and shotgun barrel-The clamping halves are held together with steel cap head screws-Extension clamps are recommended for extension tubes that extend beyond the end of the barrel-Also recommended for Remington applications due to the shallow threading on the Remington magazine tubes-Rail on both sides