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 frame with 2 inches, no dark corners. Specifications: Condition: 100% Brand New Material: Aluminum Alloy Weight: Approx. 56g / 2.0oz Color: Black External 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 Thread Package list: 1 * 2" to M42*0.75 Adapter Note: This auction only for the M42 extension tube, others(the camera adapter, the filter and the camera)just for demo. 1Thickened aluminum magnesium alloy, solid and lightweight. 2The front end is embedded with 0.75 thread, which can transfer the filter. 3Advanced hard plating technology, the entire surface is sanded black. 4CNC precision integrated precision manufacturing. 5Full frame with 2 inches, no dark corners.