The Geoptik 2" Filter Slider for Nadirus Dobsonians allows you to easily switch between up to four 2" visual filters. Its low profile of 11mm means that it will not interfere with the light beam coming from the primary mirror.
The sliding mechanism is on rails for smooth operation and the filters click into place for optimal positioning. The whole unit is made from anodized aluminium.
It is possible to mount the slider on other tubes which have a low-profile focuser with a rectangular base. The interaxial distance of the mounting holes is 91mm x 55mm.