Lacerta 30 cm Long Dew Heater Compatible with tubes 3 cm wide and 100-130 mm in diameter. Requires 5V from a USB power source, preferably operated from a power bank.
Anyone who has observed in the autumn-winter cold knows how much of a problem dew can cause. A dew shield provides some protection, but here is the "real" solution. Dew heaters are small heating pads or heating wires that keep optics warm. They can be attached around the eyepiece or tube using Velcro straps. Highly recommended for Schmidt and Maksutov-Cassegrain telescopes, where the corrector lens is particularly prone to dewing, but also useful for refractor telescope owners.
The dew heater should not be operated from a computer as it may cause damage!