This is the Castle Creations Sidewinder SV3 12V electronic speed control.
Includes: Sidewinder SV3 12V ESC with 13 gauge Battery Wires with Pre-Tinned Leads, 4mm Female Bullets for Motor Connection, Receiver Connector On/Off Switch and Instructions
Requires: Battery connectors
Input Voltage: 2S LiPo minimum, 3S LiPo maximum, 9 cell NiCd/NiMH
Reversible: Yes, with lockout
Dimensions: 1.93x1.48x0.79 (49x38x20mm)
Weight: 1.96oz (55.5g) with 5 (127mm) long battery wires and no battery connector