The Lumicon Female T-Thread - 1.25" Female Adapter threads onto male T-Threads (42mm x 0.75mm) and accepts 1.25" eyepieces accessories. It is thus a T-thread visual back for 1.25" eyepieces.
Total length = 38.1mm (1.5"); Weight = 1.3oz. Made of black anodized aluminum. Features a brass locking thumbscrew.
Manufacturer part number: LA1070