M48 2" to T2 (M42) Adapter Ring Nikon and the back focus becomes

and the back focus becomes 81

In particular

14 arcseconds

Integrated flattener with factory-set optimized distance to the objective for optimal sharpness in the field

it shows its full performance when used with a tripod

M48 2" to T2 (M42) Adapter Ring Nikon and the back focus becomesThis adapter ring turns a female T2 thread into a male M48 thread or a female M48 thread into a male T2 thread. It is very versatile and allows a variety of adaptations especially in combination with other M48 and T2 adapters. Features: T2 connection for filter wheels with female M48 thread T2 adaptation for focusers with female M48 thread Extension to M48 for focusers and adapters with female T2 thread Specs: Male thread telescope side: M48x0. 75mm