While most welding helmets come with the lenses installed if you want to replace them, here’s what you need to do:
If you’re adding onto an existing lens, then the additional one will be installed inside the helmet as opposed to outside.
Locate the tabs at the sides of the lens mount. These should be at the back of the helmet.
This is where you will attach the lens into the tabs and make sure that they are adequately locked in.
Finally, you need to wear the helmet and test it out to make sure your new lens is placed fine and is functional.