Features: 1. M42*0.75mm thread is divided into inner-ring and outer-ring double-layer structure. The camera angle can be adjusted conveniently by fixing the relative position of the inner and outer-ring with 3 screws. 2. The whole is black aluminum alloy and will not fade. Do not hurt telescope thread, two-layer thickened aluminum alloy is very strong, excellent technology. 3. Precise fit and solid connection, directly mount adapter and no adjustments required. 4. Precision all-metal construction with close and smooth combination for secure and solid fit. 5. Applicable models: for Nikon AI mount cameras and telescope with standard 1.25 inch eyepiece port. Specifications: Condition: 100% Brand New Material: Aluminium Alloy Color: Black Model: T2-AI Size: Standard 1.25inch Mount: AI Mount Thread: M42*0.75mm Suiatble for Nikon AI Mount G/S/D Series Camera Package List: 1 * AI Mount Adapter Ring 1 * 1.25inch Internal Thread Bracket Note: 1.Although the lens is physically suitable, automatic aperture, autofocus, or any other function will not work properly with this adapter ring. .2. Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.