[b]About Agena Dew-Ninja Dew Heaters[/b]Agena's Dew Ninja Dew Remover is a thick film dew heater band manufactured for operation at 12 volts DC. It prevents dew condensation from forming on the glass surface of your optical device. The heating element provides even heat distribution without localized hot spots or burnouts. These are power-efficient strips that will not result in unneccessary drain on your battery or power supply which is especially important if you power your telescope and accessories in the field.A key feature that differentiates this product from other commerically available dew heaters is the inclusion of an inline stepless rheostat that allows you to vary the power provided to the heater strip, providing just the right amount of heat for your optical setup. This eliminates the need for a separate dew controller (which start off at about $100). If you use more than one Dew Ninja heater strip on your setup, you can individually control their power output as opposed to some dew controllers that only allow you to vary the output of one or two channels.Agena Dew Ninja strips are manufactured to very high quality standards. Each heater has a hook-and-loop self fastener strip on one side for easy attachment and comes with a 1 or 3 foot cord (varies by model - see table below).[b]B. Powering the Agena Dew-Ninja Dew Heaters[/b]The power cord on these dew heater bands terminates in a DC 5.5mm x 2.1mm [b]female[/b] power connector. It also includes a separate DC male to RCA male cable.If you have a power supply or dew heater controller with RCA female jacks, use the included DC-RCA cable mentioned above.These bands can also be powered from many commercially available batteries, power tanks, or cigarette lighter adapters that have a 12V 2.1mm pin power output. However, almost all of these devices have a [b]female[/b] power socket as well. [list] [*]Many of these (examples: ASIAIR-Pro/Plus, Agena AstroCell portable batteries, Pegasus Powerboxes) come with one or more male-male 2.1mm power cables, in which case you do not need any additional cables. [*]However, if your power source does not come with a male power connector or cable, you will need to purchase a 2.1mm male-male cable separately to power these. [/list] Note that these dew heater strips do not come with any power supply. You cannot run these directly from 110/220V AC, USB, or cigarette-lighter sockets and no other power cords are included.