The R2104GF receiver is a 4 channel receiver that is designed to be used with Futaba's S-FHSS or FHSS protocol transmitters. It has two operating modes - Normal and High Speed. In Normal mode, it can be used with any servos or devices compatible with a 13.6ms frame rate. In High Speed mode, the receiver only accepts digital servos, including the BLS series, and most brushless ECSs. In High Speed mode, the output frame rate is 6.8ms.

Specification : 

Frequency - 2.4GHZ band

System - S-FHSS/FHSS (auto detection)

Operation Mode - Normal/High Speed (auto detection)

Power Requirement - 4.8 or 6V

Current Drain - 30mA

Specification : 

• Mode: Normal / High Speed
• Modulation: S-FHSS & FHSS
• Weight: 8g (0.28oz)
• Voltage: 4.8 - 6V
• Channels: 4
• Operating Current: 30mA
• Dimensions: 39 x 26 x 10mm (1.54 x 1.02 x 0.39")
• Frequency: 2.4GHz