Avoiding water equipment leaves two distinct choices: passive bedding and powered airflow. Neither should be described as waterless refrigeration for your mattress.
Passive layers
A cool-feeling cover can alter the initial surface sensation. A foam topper changes cushioning. These may be useful purchases, but a gel label or breathable textile does not establish a sustained temperature drop in your bedroom.
If your mattress already feels too soft, adding foam is a questionable way to pursue cooling. Start with upper bedding and room conditions instead. If it feels too firm, choose the topper for its comfort change and evaluate warmth separately.
Powered airflow
An under-cover air system moves room air through the bedding space. That can suit someone who wants airflow without a reservoir, but it still adds a fan, power supply and nozzle. It cannot provide the same below-room-temperature cooling mechanism as a refrigerated water circuit.
Before ordering, check whether your room regularly exceeds the manufacturer’s recommended cooling conditions. Decide whether the added fan sound and moving air are acceptable to both sleepers. A returnable purchase with the correct bedding accessory is more useful than an impressive maximum-airflow figure for a setup you will not tolerate.
Identifiable options to compare
BedJet 3
Airflow under the covers. It does not refrigerate room air; BedJet says cooling is limited in bedrooms regularly above 79°F. Manufacturer details . Search Amazon for this model .
LINENSPA Gel Memory Foam Mattress Topper
A foam layer for changing cushioning. Its gel label is not proof that it keeps every sleeper cooler all night. The manufacturer specifies spot cleaning for the foam. Manufacturer details . Search Amazon for this model .
These are researched examples, not a tested cooling ranking or a claim of current stock. Match the model, size, contents and seller in search results.
For the differences between passive fabric, cushioning and powered cooling, see our cooling mattress pad buying guide .
See Also
If you want to pressure-test this shortlist, read Thin vs Thick Cooling Pads: Decide How Much Feel to Change, Travelling With a Humidifier: Need, Power and Cleaning Checks, and Cooling Layers for Stomach Sleepers: Check Softness First next.
For more context beyond the main ranking, Warm Mist Humidifier vs Evaporative Humidifier and Best Mattresses for Every Sleep Style add useful comparison detail.