Surelock Security SureDry Dehumidifier Black 12" Keep the moisture out of your SureLock safe and protect what can't be replaced, with our Supply Series Dehumidifiers. Our moisture-wicking SureDry technology defends your treasured possessions from rust and potential ruin. The 12" dehumidifier will cover 100 square feet of space. The 6.50 foot power cord gives you the flexibility to position your dehumidifier anyway you need to.