I'm in the middle of building a giant 6ft x 4ft laser cutter and I got an F4 100W CO2 laser from lightobject.com and some mounts for the tube. The mounts have a sharp v-shape and I wanted a full contact solution so these just slide right over the orginal mount and I put in some track and mounting holes so you can use a spring or rubber bands to hold the tube down. The F4 tube is 80mm in diameter so you can use this for any other tube in the same size range.