This module is designed to work with more than one version of the MX3. Its connectors are also labeled to indicate a relationship that could potentially damage your laser module and/or MX3 control board - READ AND UNDERSTAND THE INSTRUCTIONS BEFORE POWERING UP! Just reading the labels for the ports on each of the boards suggests the connection is *not* correct. Sparse as they are, the instructions provide enough information to identify your control board and properly connect the laser control board (they are in the PDF files on the included CD. More on that below). However, it is a clean little module. The control board can remain on the router when the laser is not in use; However, the laser replaces the spindle motor as the tool head and the Z-axis is not used with a laser - be sure to unplug the Z-axis servo cable when using this beast to avoid the hassle of unintentionally moving the tool head. up or down in your gcode - once focused the laser doesn't need to move in the z-axis. A design where they could be adjusted simultaneously would be great, but for the money I'm not complaining. The laser is easy to focus and the configuration for Mach 3 is included on the hard drive (yes, hard drive. Tiny CD. It would be advisable to switch to flash drives as most modern laptops and many desktops no longer have optical drives, but I digress). This is not a "magic bulletβ for a manufacturer interested in laser cutting. It cuts paper with ease - and that's pretty much all I've done with it so far: made a few stencils - but I see the possibilities and I have a few projects I've seen on Instructables that I'm trying to cut can thin pieces. Wood and thick cardboard - I will update my review as soon as I have experience. The Grim? Knowing what I know now, will I spend money on it again? Yes. I think I would