This variable adapter connects accessories with T threads. It is an assembly of 3 elements:
- Bottom barrel with female T thread (M42x0.75)
- Top barrel with male T thread (M42x0.75)
- Locking ring to lock the top barrel in position.
The variable length of the adapter between 24 and 35 millimetres is particularly useful for telescopes that use coma correctors or field flatteners where the distances are critical.
