Male thread - M42X0.75; Female thread - M42X0.75; eliminates a range of focusing problems
The extension tube has a T2 interior thread and a T2 exterior thread for elegantly solving spacing problems in astrophotography.
Use this extension tube for getting the correct image scale or the exact spacing required for reducers or field flatteners
T ring for Nikon-F SLR/DSLR: Compatible with Nikon SLR/DSLR Camera with F-Bayonet (Please Attention); including Camera Nikon D90 D80 D70 D60 D50 D40x D40 D800 D700 D600 D300s D300; Equipped with one hex wrench that achieve camera's easy angle adjustment
Quick & Convenient Installation: Just clockwise tighten T ring to Nikon F-Bayonet DSLR/SLR Camera via camera connecting thread after aligning camera lense bayonet; Other end connect with telescope accessories includes M42x0.75 Male Thread like T Adapter