Guns.com The SafElert will even send you weekly humidity status reports to let you know if it's time to change out your safe's desiccant if you need any, and it will notify you of sweeping temperature changes in case of a fire or flood. The unit is battery ...
Deadspin A desiccant like DampRid will help those sorts of matters greatly. (This is also a thing for those of you who live in basements and/or swampy climates to know about.) It also bears mentioning that those scented plug-in things and sprays are terrible ...
