Digital Eyepiece Camera
They offer Plug-and Play compatibility and come with user-friendly, efficient imaging software. 
An excellent choice for research, medicine, education and industry applications.  
Compatible with Windows XP, Vista, 7, 8, Linux and Mac operating systems.
Plug-and-Play compatibility allows you to connect more than one cameras in one PC at the same time.
Includes:
0.5x C-mount relay lens; fits 23mm tube.
6' (1.8m) USB cable.
Two eyepiece adapters: 30.0mm & 30.5mm.
CD with software, driver and user manual.
Digital eyepiece camera.
Two rubber seal rings.
Stage micrometer with 0.01mm increments.