While the provided glasses greatly cut back on eyestrain from the laser, I still felt some irritation and “after burn.”
I bought a set of 5 gel sheets used by photographers and stage lighting techs, mostly to turn a bluer light to something yellower (lower the color temperature). From Amazon:
https://www.amazon.com/dp/B08814CBJSpsc=1&ref=ppx_yo2ov_dt_b_product_details
although now it seems to be a set of 4 sheets.
I found that all of the sheets together work quite well for the A40640 laser. I hand hold a stack about 3” wide taped together at the corners in front of the goggles to view a cut in progress, and will also use the sheets over an acrylic panel for viewing when I build a cover box.