The 30 mm extension tube screws directly into a standard 1.25″ filter thread, for example on an eyepiece, adapter, or other accessory.
It is used to extend the optical path when the focus position needs to be shifted or when a specific spacing between optical components is required.
It has an M28.5×0.6 thread on both ends, so multiple extension tubes can also be connected together.
Specifications:
Length: 30 mm
Thread: M28.5×0.6 on both ends
Material: aluminium
Colour: black