This is Hobbywing Xerun XR10 Pro 1S HD 1/12 Sensored Brushless ESC.

Features:
Word's Champion's choice, ROAR APPROVED
Redesigned new architecture platform 
40% smaller in volume* (*6mm shorter,  6mm smaller in width)
24% lighter in weight (12g lighter than the previous generation)
Premium MOSFETs (Toshiba MOSFETs)
Super BEC. Internal BEC features booster circuitry can output the current/voltage of up to 6A/6V and power various servos without connecting any extra receiver battery.
Built-in electronic switch (with a lifespan of over 50000 on/off cycles, dust-proof and shock-resistant design)  
Built-in capacitor module saves space and weight making the wiring simple and neat.
PWM Frequency tuning - guarantees precise and accurate throttle and brake control for all classes of competitions (esp. the Stock class).
Maximum Cooling performance - Separate Programming/Fan Port
The separate PRG/FAN port on the ESC can power an external fan to maximize cooling performance or connect the ESC to an LCD program box or WiFi module for ESC programming.
Specification:
p/n: 30112603
Application: 1/10 - 1/12 Brushless sensored system
Cont.: 120A
Peak Current: 830
Input: 1S LiPo/3-4 Cells NiMH
BEC output: Switch Mode:6V/3A
Programmable: Yes
Firmware update: Yes
WiFi Module: Enabled
Dim.: 37.5x31x15.9mm
Weight: 35.6g 1.26oz

Includes:
(1) ESC
(1) RX Wire
14 Ga & 12Ga Wires (Two Types)
Bonus accessories (heat sink, etc)
User's manual
Decal