CNCOLETECH CO2 Laser Lens Dia:15mm FL:2 or 50.8mm Laser Mirror CVD ZnSe Focus Focal Lens for CO2 Laser Engraving Cutting Engraver/Cutter 40W-200W

smaller than others I have ordered but still worked

Yeah this is not 12mm and therefore unusable junk.

Identical to the name brand one for my laser, at a fraction of the cost.

Bought this to replace my damaged 2 OEM lens for my Thunder Laser. I did a ramp/focus test using LightBurn and found my new lens to be focused tightest at 5.5mm (vs. the nominal 6mm the machine is set up for). I run it at 5.5mm for precise work, but put it 1mm out of focus at 6.5mm when I sometimes want a wider beam for engraving. Overall, it seems to work well.

Great value for a good quality lens. Focus was clean on install. Coating is more substantial than other inexpensive lenses that I’ve tried. We’ll see how it’s going in a few months.

Works