Check the listing for details. DC Dual Flasher Circuit (Variable Speed). Condition: New. Listed at 11.99 USD. For sale in this listing is a DC Variable Dual Flasher Circuit, controlled using a PCB-mounted trimmer potentiometer. These are hand-made right here in my shop near Longview, TX. Not mass-assembled in China. I've assembled and tested each one for quality. I will also be the person you talk to if you need help installing it on your application. Now isn't that worth the extra dollar from "the other guy?" If you're still looking to save a couple bucks, I do also have a fixed speed flasher here: DC Dual Flasher Supply voltage range is 5-16 volts DC only. Some applications for this device include warning signs, bicycle lights, model train signals, RC cars, or planes, party strobes, automotive flashers, lighting beacons, and more! ***ATTENTION*** Close adult supervision is required with this and all electrical products. With less than 5 volts, the flasher will not work. More than 16 volts will destroy the unit. Reversing the Polarity or supplying it with AC (Alternating Current) will destroy this unit! Any questions about the power source, please ask me first before you buy! Output voltage will be approx. 0.600 volts lower than the supply voltage, maximum of 500mA. (0.5 Amps) No power supply is included with this device, you must provide your own source of power. The battery and lamps in some of the photos are not included with this device. This product will provide an oscillation of DC power, ample enough to flash two lamps opposite of each other, or series of lights in parallel. The default frequency range for this flasher is as many as 20 cycles per second, and as few as one cycle per second. Longer and shorter cycles are possible upon request. The cycles are adjustable with the potentiometer. For $3.00 more you can opt for a panel-mount potentiometer instead, with leads up to 24" (61mm) in length. DC Dual Variable Flasher, w/ Panel-Mount Potentiometer - https://www.ebay.com/itm/194109832836 Please note: This device is sensitive electronic hardware. Therefore it is being sold as New, Assembled and Tested. I will guarantee that it arrives at your door ready to work. But once you have taken it out of the sealed Anti-static bag and connected it to power, you are assuming all responsibility for its function after that. If you are unclear as to how it operates, please ask me before you break the seal on the bag. You should also have a solid understanding of the devices you are connecting to this device as well. (i.e. LEDs will require a resistor in series, or AC power adapters will not work, etc.) From this point forward I will no longer offer refunds on sensitive electronic devices that have been removed from their sealed bags. I have made my skills and resources available to anyone who comes to look at my listings for free whether they purchase my products or not.