For all sizes of aquariums not just the JBJ nano cubes. This unit is a breeze to use. Able to give you instant readout in your tank.
We also have other affordable thermometers for your aquarium.
We are a Dealer/Reseller of the Transworld Aquatics Line of JBJ Products. For warranty information please contact us and we will fwd you to the correct place. Most of their products carry at least a 1 year warranty.