Lumicon Female T-Thread - 2 Inch Female AdapterLumicon Female T Thread 2 Inch Female Adapter Lumicon Female T Thread 2 Inch Female Adapter threads onto male T Threads and accepts 2 telescope eyepieces & accessories. Overall length is 2. Applications: To use 2 eyepieces on Lumicon 1. 25 Multiple Filter Selector & Solar Prominence Filter; to use 2 eyepieces on Lumicon 2 Multiple Filter Selector when the photographic adapter, the LF5020, is installed.