Features:Thickened aluminum magnesium alloy, solid and lightweight.The front end is embedded with 0.75 thread, which can transfer the filter.Advanced hard plating technology, the entire surface is sanded black.CNC precision integrated precision manufacturing.Full framewith 2 inches, no dark corners.Specifications:Condition: 100% Brand NewMaterial: Aluminum AlloyWeight: Approx. 56g / 2.0ozColor: BlackExternal Thread: M42*0.75mm (Suitable for connecting the bayonet of T2 SLR camera)Internal Thread: M48*0.75mm (Suitable for connecting with filter)T-head Specification: 2 inches(Suitable for connecting astronomical telescope with 2 inch connector)Matting: Internal Full Matting ThreadPackage list: 1 * 2" to M42*0.75 AdapterNote:This auction only for the M42 extension tube, others(the camera adapter, the filter and the camera)just for demo.