650nm Laser Diode Red Laser Tube for DIY Laser Module (4pcs) - Amazon.com
This Maker Built a Gas-Mixing Device for DIY Laser Tubes - Hackster.io
JK100W Laser Tube
Amazon.com: OMTech Upgraded 100W CO2 Laser Engraver Cutter 20" x 28" Laser Engraving Machine with Ruida DSP LCD Display RDWorks V8, USB Port, Air-Assist, LightBurn Software for Windows Mac OS Linux(MF2028-100)
Homemade CO2 Laser, part 3 - YouTube
Building A CO2 Laser In A Hardware Store | Hackaday