The Powermate T-ring adapters allow imaging through Powermate lens assemblies. Tele Vue T-Ring Adapter (PTR-2200) replaces the 2" eyepiece holder on the Tele Vue 2x Powermate (PMT-2200) with a 42mm (M42x0.75) male T-Ring thread for photography. Use of this adapter requires an additional M42 T ring for your specific camera (not included). Cannot be used with wide M48 T rings.