This is the Hobbywing Platinum Pro V4 25A ESC, for use with 200-300 sized Helicopters.  

Innovative Heat Dissipation Structure 
The innovative "duo" stacking structure allows all components on both sides of the printed circuit boards to quickly conduct heat to the aluminum case.

Excellent Motor Speed Governing 
The high performance 32-bit processor, combined with advanced algorithm, makes the motor speed-governing excellent for different conditions. With the adjustable sensitivity of speed-governing, every pilot can find the most suitable settings for his helicopter.

Super Soft Start-Up 
The Platinum 25A makes the motor start extremely soft and avoids tail-drift issues. The start-up time is adjustable within 8 to 25 seconds. This will definitely create a perfect starting point for every flight.

Super BEC 
The built-in switch mode BEC with a continuously adjustable output voltage, range from 6V or 7.4V . It is certain to put out the power you need for rapid, precise servo operation.  

Great Current Endurance 
A high-quality and high-voltage MOSFET with a great current endurance guarantees the ESC's safety especially in a extremely high power demanding situation. 

Built-in Sparkproof Circuit 
Built-in sparkproof circuit effectively eliminates sparks produced at the "powering-on" moment and prolongs the connectors lifespan. 

Specifications: 
Main Applications: 200-300 Class Helis 
Governor: Internal 
Built-in BEC: Yes; Switch Mode: 6V or 7.4V, 3A 
Continuous Current: 25A 
Cell Count: 3-6S 
Case: Plastic
Programming: LCD Program Box 
Peak Current: 40A 
Weight: 27g 
Dimensions: 47x22x10mm 
DEO Technology: Yes 
Spark-Proof: Yes