This simple Astroadapter uses the MeoStar's bayonet mount, no tools are needed, and you can effortlessly switch between your Meopta eyepiece and telescope eyepieces as your needs change. This product is only the adapter, and an eyepiece is required. A single thumbscrew is used to hold the eyepiece in the holder, so it won't fall out. Since the adapter uses the MeoStar's bayonet mount, there are no tools needed and you can easily switch between your Meo