You are looking at a NEW Helibatics SimonK 20Amp ESC with 5V/3A BEC NEWEST (version BS N-FET V2014-06-18) firmware flashed (and tested) for multicopter!

This is The BEST 20A ESC for multirotor!  Read on to understand why:

These are identical to the HobbyKing F-20A which have a 100% N-FET design, and a Crystal Oscillator/Resonator for PWM range accuracy in all temperatures.  I don't think there is a better 20A ESC for the price.  I investigated and evaluated many of the ESC's available before deciding on this on.  I believe it's the best, and I think you will too.

With the included SimonK firmware (bs_nfet.hex), these ESC's are perfect for any multicopter device requiring up to 600Hz response, such as a tricopter, quadcopter, hexacopter, or octocopter.  These work great with 3DRobotics DIYDrones APM2.X series UAV controllers, DJI Naza, and many others.

This hardware, with the SimonK firmware, gives you the perfect solution for multirotor use:

• Highest efficiency 100% N-FET design.
• Highest accuracy with Crystal Oscillator/Resonator (Temperature won't affect the PWM operating range like other cheap ESC's).
• No low voltage cutoff, because any cutoff in a multirotor = crash.
• No over temp cutoff, because any cutoff in a multirotor = crash.
• Super high refresh rate, no buffering of the input signal, resulting in up to 600Hz response rate.
• 16KHz motor frequency, giving fastest response of the motor, and quietest operation as well (no 8KHz squeal).
• Super simple, foolproof operation! Nothing to program other than the throttle range.
• You can easily upgrade the SimonK firmware yourself using the Hobbyking Turnigy USB Linker.
• Don't buy a 20A multirotor ESC that doesn't meet all these criteria!  There are a lot of low quality 20A ESC out there!

ESC Specs:

• Max cont. current: 20A
• Peak current: 30A (10s)
• Voltage: 2-4S lipo, 5-12 Nicad
• BEC: 5V/3A
• Size: 54x26x11mm
• Weight: ~30g

NOTE: Before you buy these, you should make yourself familiar with the somewhat experimental nature of the SimonK firmware. This software pushes the motor response to the limit, so there may be motor and prop combinations that won't work.  Due to the lack of overcurrent/overheat/low voltage sensing (needed for multirotors), it's easier to destroy the ESC and possibly the motor too.  I'm can't tell you what will or won't work, other than the motors I sell that I've personally used, so please consult the main SimonK threads on various forums for more info. Neither I, nor SimonK will be responsible for any damage that may occur, so know and accept the risks before using these.  That said, I've personally had fantastic results with this firmware and wouldn't use anything else!  The latest version of SimonK has resolved most if not all known issues, so it is very safe to use.

Please go to this for shipping and combined shipping content: http://stores.ebay.com/HeliBatics/Payment-and-Shipping.html

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