if u want the RH to drop fast, use thirsty hippo. there are diff sizes to cater to the size of ur box. But try to use those sachet ones as the box type maybe too dry... My sachet had been used for 5 months liao still can maintain RH about 45-55%. I open my box about once a week. But in the long run, like what most will say here, get a dry cabi to save ALL the trouble... just my 2 cents.