Flashlight and Laser Sight Mount with Barrel Adapter This mount is for mounting flashlights and laser sights with a one inch diameter directly on to the barrel of a rifle or shotgun. The mount can be separated into two separate parts. The weaver type ring mount can be used on any picatinny rail base. It is made from strong light weight aluminum.
https://www.amazon.com/Flashlight-Laser-Sight-Barrel-Adapter/dp/B000MH4CN2