SPT C35 35W CO2 Sealed Laser Tube for Small and K40 Laser Engraving Machine - LightObject | Professional Laser Cutters and Engravers Solutions
VEVOR VEVOR Laser Tube 40W CO2 Laser Tube 700mm Glass Laser Tube Professional Special Coating Technology Tube Laser Cutting Tube for Laser Engraving Machine and Cutting Machine | VEVOR EU
Laser-tube | Hackaday
Co2 Laser Tube 40w 50w 60w 80w 100w - 100% Power 40w Co2 Laser Tube Metal Head - Aliexpress
Replacing the K40 tube (want to make sure I'm getting the right thing/right size) - Lasers - Maker Forums
K40 eBay Chinese CO2 Laser - Building Tube Hangers Alignment Part 3! - YouTube
Custom laser tube mounts for K40 - had trouble aligning my new 45w tube with stock clamps. : r/ChineseLaserCutters
TEN-HIGH 50W CO2 Laser Tube 800mm D50mm, Wires Preconnected with Coating, for Laser Cutter Laser Engraving Cutting Machine