Xing Laser D20-F150 Welding Focus Lens for Air Cool Welding Machine

Part Name: D20-F150 welding focus lens
Compatibility: Fits 1200W air-cool welding machine gun head only. 
It does not work on water-cooling, pulse, or other machines.
The lens has concave and convex sides; the convex side always faces the rear part of the gun.
Recommend Replacement Days (4 - 8 hours using daily): 60 - 120 days or longer if still clean
Note: Specifically compatible with Xing Laser machines; may not fit other brands.