For cool mist desktop humidifiers for study rooms, useful comparison points include placement, dimensions, power method, capacity, controls and the specific functions represented by the search.
Catalog options relevant to this combination include Mini USB Desk Humidifier with Night Light, Mini USB Negative Ion Potted Air Humidifier, and Mushroom Desk Humidifier with LED Light. Their exact specifications can differ, so use the individual listings for final product details.