I saw “40 hours usable per mask” and “all masks should be cleaned with 70% alcohol or soap and water, and dried naturally for up to 24 hours” in the description. So, I went to check what the manufacturer said, and
“Our LIGHT SE, POCKET & KIDS masks can be washed in a washing machine for up to 5 - 10 wash cycles, at 30 - 40 degrees Celsius with water only. Please note that masks will have a reduced filtration of 70%. To keep 99.3% particle filtration (PFE) and 99.9% bacterial filtration (BFE), you can wear our mask for up to 40 hours and after that, they have to be thrown away. The masks can be disinfected with a 70%+ alcohol solution from the inside and outside but still need to be thrown away after 40 hours.”
So each mask is usable for about a week. You could machine wash it, but then it wouldn’t protect you.