Fully metal construction and anodizing aluminum process, durable for long time use
Use this extension tube for getting the correct image scale or the exact spacing required for reducers or field flatteners
The extension tube has a T2 interior thread and a T2 exterior thread for solving spacing problems in astrophotography and eliminates a range of focusing problems
Astronomical T2 thread Extension Tube;male thread is M42*0.75mm female thread is M42*0.75mm
Use this extension tube for getting the correct image scale or the exact spacing required for reducers or field flatteners; provides extra focuser back travel which is often needed for short-range terrestrial viewing or astrophotographic applications