Wisesorb 2 LBS Activated Alumina, Alumina Desiccant, 1 Quart Reusable Dessica...

Works great in both my gun Safe and 3D printer. Works just as planned and sucks up the moisture quickly and daily.

It's more expensive and has no color indication so I was skeptical when I got this but figured I'd indulge my bougie impulses and they were well rewarded. I got these for my 3d printer filament dry boxes and it's night and day. I live in the EXTREMELY humid S. Eastern US where the LOW, indoor relative humidity is in the 60% range. Filament starts stringing like crazy after a few hours in the open. To test efficacy I used the exact same desiccant holders and swapped out the silica for activated alumina. My K2 Plus CFS used to bottom out at 15% RH with 3 separate added desiccant holders plus 4 in spool ones. My dry boxes were 20% Just using 2 of them but filled with this stuff took me down to 5% and whenever I swap spools, it gets back down to 5 much quicker. My dry boxes go lower than the minimum 10% my cheapy hygrometers can read. If you're concerned about color indication, don't mix the silica but instead they also sell RH test strips you can use. However what I've found by switching to this is the color does matter. Add desiccant until you reach the desired RH. Whenever that begins to rise it's time to replace/recharge it. The part we care about is the humidity and for filament or electronics, the color indicator shouldn't be what tells you that it's too high. It's also easier to 'recharge' as the color used for indication is toxic while activated alumina is pretty much harmless. While it's more expensive, you get a much better value for the money which does a better job and lasts longer. The filament boxes show petg. I had honestly just thought my hygrometers bottomed out at 20% until testing the alumina. Plus this Wisesorbent is cheaper than the other options.

Works excellent as desiccant for my 3-D printing filament. Better moisture control than the silica based desiccant. I wish it had an indicator to tell when it is absorbed all the moisture it could. For now, I mix it in a combination with color changing silica desiccant.

Excellent stuff, good deal. Works noticeably better than silica.

This stuff is insane. I live in a very humid tropical zone with 75% RH and the AMS 2 Pro was constantly measuring around 25-35% with weekly 12 hours filament drying sessions at 60° degree C (silica only halfway dried) Immediately after replacing the silica with the alumina, the humidity started to go down. After a couple hours the AMS reports 10% and the same on the meter. Never seen such numbers before with the silica, I’m beyond impressive how well this stuff works. I still need to check after 15 days or so if they are still efficient. This is how long I would need to replace the silica with fresh ones before drying them. Supposedly the alumina can absorb more % of their weight. Cons: -When poured out of the container there is a small dust that can be picked up by air drafts, not sure how safe is this to be around with. -The beads seem to be quite fragile, not sure how well they can handle continuous handling and re-drying on the oven. -Expensive but not by that much

Perfect for my 3D printer filament

I am using this as a replacement for silica beads used to dry plastic 3d printing filament. This has kept filament that was dried to 10% humidity at that level for several weeks before needing to be recharged.The only downside is that silica will change colors when it has absorbed too much moisture and this does not.

Exceptional desiccant. Love that it is "rechargeable" (dryable) to be reused. How many times, I am not sure, but research seems to indicate that it can be dried repeatedly. I do wish there were some color-changing desiccant mixed in, but I've simply added another type of desiccant to give me an approximate value. I believe that color-changing desiccant holds less water than alumina (aluminum oxide), so the alumina should still have plenty of absorption capacity when the color-changer indicates that it is "full". Note that this is "low dust", and while non-toxic, the dust can be physically harmful. Wear a mask when handling. Lastly, when this stops working, it could be crushed into a powder and used as an abrasive. After all, it's just pellets of aluminum oxide. In my opinion, this was an excellent purchase and well worth the money.