The RX631 from SANWA is a 6 Ch Full-Range receiver made especially for the SD-10G. It uses the FHSS-3 2.4 GHz system; the fastest system available. It is a slim receiver that fits in tight spots the 10channel receiver will not and features our industry leading interference resistant 2.4GHz technology. It has exceptional tolerance for temperature and can operate at voltages under 3.0 volts. This FHSS3 receiver is also compatible with the SD-10G Model "Safety-Link" and has easily programmable failsafe on all 6 channels.