I put one in each of my two airtight 3D printing filament boxes, straight from the sealed bag.A couple of days later I checked the results via the monitors that are in there. In both boxes the humidity had spiked even higher than the humidity outside of the box. The smaller box went from 34% to 58%!I now have a lot of filament to dry, not to mention the silica gel that was already in the larger one.The indicator dot on both bags was not pink (which I checked for) but had turned beyond pink to mustard. I did not realise it should have been blue instead.If you consider buying these, at least dry them thoroughly before use.Update: I cut open the bags (they contained 500g of silica gel beads each, as advertised) spread the contents over 3 baking trays and put them in the oven at 100°C for a few hours to thoroughly dry. This did the trick. Bought some organza drawstring bags to put the beads in afterwards. All in all a lot of work and extra cost.

The bags were delivered in a sealed plastic bag, so I assumed they were dry. They were not. You need to dry them first in the microwave. Be careful not to put them in too long, 8-10 minutes is way too long on 750W and will damage the bag. 5 min max per cycle, then cool.Also there is no color changing spot on the bags I got. There was only a piece of cardboard behind the hole. These could be fake. In any case I suggest getting orange or blue color changing silica gel, so you can see if it needs be charged.

Följ för allt i världen inte instruktionerna för då har du silikon kulor i hela micron plasttyget smälter och allt åker ut... Riktigt svårt, nästintill omöjligt att torka i micron

Works great . Rather than put them in the microwave I'll put them in top of my radiators next time as made the microwave smell but nothing drastic

Prodotto davvero eccellente. Lo vendono da usare in macchina ma io li ho messi al interno di due armadi blindati; che quindi al loro interno non c’è molto ricambio d’aria; e sovente si presentava muffa e odore di chiuso. Da quando ho messo questi sacchetti ho risolto il mio problema. Per adesso sono passati mesi e non ho dovuto neanche riattivarli passandoli in microonde. Molto consigliato

La uso en el coche, ya no huele a humedad, y, no desempaña tanto.

Conforme à la description