The focuser is attached to every telescope near the focal point of the light-collecting optics. As the name suggests, eyepieces can be inserted in the focuser. For astrophotography, the focusers hold cameras and bring them into focus. Therefore one speaks of focuser instead of focuser.
The UltraLight focuser is suitable for these types of telescopes: SC, RC (only with M90 x 1 connection), Newtonians from the SkyWatcher brand.