This is the Spektrum SRS4210 DSMR AVC Surface Receiver. Now get stability control for ANY vehicle in your collection! You can have the stability control of AVC™ (Active Vehicle Control™) technology in any vehicle just by adding the SRS4210 receiver and binding it to an AVC compatible transmitter. AVC technology creates a more enjoyable driving experience by managing the vehicle’s driving characteristics and attitude. This translates into more control for you and a more manageable vehicle in all driving environments. 

Features: 

• 4-Channel DSMR receiver and AVC technology in a single, lightweight unit
• Fully adjustable - set the precise amount of stability you want on the fly
• Works with any RC car, truck, or buggy
• No complex setup required - just install, bind, and calibrate
• Compatible with all DSMR and DSM2™ surface transmitters
• Reliakote™ waterproof coating on the electronics

Specifications: 
Type: 4-channel DSMR stabilization receiver 
# of Channels: 2 with AVC active (4 with AVC disabled) 
Modulation: DSMR/DSM2 
Band: 2.4GHz 
Length: 1.43 in (36.3mm) 
Width: 0.96 in (24.4mm) 
Height: 0.51 in (13.0mm) 
Weight: 0.39 oz (10.9 g) 
Voltage Range: 3.5-9.6V 
Antenna Length: 8.27 in (210mm) coaxial