This is the Spektrum AR6210 6-Channel DSMX Full-Range Receiver. The AR6210 DSMX 6-channel receiver is a great solution for all model aircraft requiring full range up to six channels.
This DuaLink receiver simultaneously gathers information from two receivers that is processed by patent pending Spektrum software that combines it to form the most vivid picture of an RF signal. This dual path redundancy, plus the fact each of the two receivers is located in a slightly different location, exposes each to a different RF environment and creates a bulletproof RF link in all conditions.
US patent 7,391,320
Specifications:Type: Full Range Aircraft Receiver# of Channels: 6Modulation: DSM2/DSMXBand: 2.4GHzLength: 1.19 in (30.1mm)Width: 1.03 in (21.6mm)Height: 0.48 in (12.3mm)Weight: 0.35 oz (10g)Voltage Range: 3.5–9.6VAntenna Length: Main Rx: 30mm (2); Remote Rx: 30mm (2)