General Welding masks

Auto-darkening masks/helmets have transformed MIG/TIG/ARC welding in the last ten years or so, now becoming more affordable (typ. £50 budget; £200 top-of-the-range)

This is one of the best available, with a full set of controls for shade (9-13) and delay, making it very suitable for MIG welding. Also has a large visor area and side-panes + easily changeable front screens and filter glass inside. It's a Hornell Speedglass 9000 series (Swedish) and obtained for £100 on eBay when less than a year old (originally £200+) They can also be obtained with integrated breathing equipment.

Typically these types of welding mask/helmets offer fair light & vision prior to striking up, and darken down to the pre-set shade within a couple thousanths of a second... Even in normal light when not darkened they still offer full UV protection