This is the Traxxas Velineon VXL-3M Waterproof Brushless Electronic Speed Control.

The Velineon® VXL-3m™ forward/reverse electronic speed control simplifies brushless technology with easy, built-in profiles and intuitive programming. The VXL-3m uses advanced circuit design that allows sensorless brushless motors to operate with the smoothness and precision of the best brushed systems. It sets up, operates, and programs just like the Traxxas XL-5™ family of ESCs so there's no tricky new procedures to learn. Traxxas' exclusive patented Training Mode™ is also included to limit full throttle to 50% for young or inexperienced drivers. For the most advanced users, the VXL-3m is equipped with two-stage low voltage detection to allow LiPo battery use, including powerful 11.1-volt 3s packs! The VXL-3m is manufactured by Traxxas to ensure the highest level of quality and support.

Features:
Traxxas patented High-Current Connector maintains pure, unrestricted power flow from the battery to the brushless power system.
Built-in two-stage low voltage detection for Lithium Polymer (LiPo) battery use provides a clear signal to the driver that the battery pack is nearing its minimum voltage threshold.
Wide range of battery options, including 6-12 cell NiMH packs
The patented Training Mode™ is an exclusive Traxxas feature that reduces the overall power output of the VXL-3m by 50%, making it easier for new or younger drivers to control their model. When they're ready, simply change profiles to unleash full-throttle action.
Advanced circuit design allows sensorless brushless motors to operate with the smoothness and precision of the best brushed systems. There's no need for additional sensor wiring and hardware complexity.
The EZ-Set® push-button setup operates and programs just like other Traxxas speed controls such as the XL-5. This eliminates the need to learn a new set of procedures.
The VXL-3m is programmable with three drive profiles:
Sport Mode – Fwd / Brake / Rev
Race Mode – Fwd / Brake
Training Mode* – 50% Fwd / Brake / 50% Rev
Multi-color LED provides clear feedback
Two-stage thermal shutdown protection protects the VXL-3m from overheating
Locked Rotor Protection™ prevents system damage by cutting power if the vehicle is stuck or the motor is bound
Battery Over-Voltage Protection™ causes the ESC to go into failsafe mode if the maximum input voltage is exceeded
Water resistant case design uses rubber seals and O-rings to protect against damage caused by water and moisture
Micro fin aluminum heatsink dissipates heat
MOSFET design provides high-current output with incredibly low resistance (.0005 ohms)
Gold plated 3.5 mm bullet connectors on 16-gauge Maxx® Cable flow full power to the motor without performance-strangling resistance

Specifications:
Input voltage: 6 to 12 cells NiMH, 2s to 3s LiPo
Case Ssze: 26.5 mm W x 46.5 mm D x 22 mm H
Weight: 38 g
Motors: Sensorless brushless
Motor limit: None
On resistance: 0.0005 ohms
BEC voltage: 6.0 V DC
Motor / battery wiring: 16-gauge Maxx® cable
Transistor type: MOSFET
Low voltage detection: 2-stage indicators, switchable (on or off)
Thermal protection: 2-stage thermal shutdown
Profile selection:
Sport Mode: 100% fwd, 100% brakes, 100% rev
Race Mode: 100% fwd, 100% brakes, no rev.
Training Mode*: 50% fwd, 100% brakes, 50% rev.
Single-button setup: Traxxas EZ-Set®
Battery input connector: Traxxas High-Current Connector
Motor connector: TRX 3.5 mm bullet connectors