Founder Optics 2.7" Dual Threaded Adapter for Reducer - DTA-RED2.7This heavy duty dual threaded (2" to 2. 7") adapter is designed to attach the Founder Optics Reducer to telescopes with a 2. 7" focuser. When doing astrophotography it is important to keep the optical chain as tight and aligned as possible. This adapter uses threads instead of screws or tension adapters for the mechanical connection, which reduces the possibility of a gap or flexing in your optical chain. Paying attention to the quality of your