This is the Tower System2.4 2-Channel 2.4GHz Receiver. **Not compatible with Futaba or Spektrum radio systems.** FEATURES: Compatible with the Tower Hobbies System2.4 model 224 2-channel pistol radio and servos with "J" style connectors Built-in "bind" button with LED indicator No crystal required Very lightweight INCLUDES: Tower System2.4 2-Channel 2.4GHz Receiver REQUIRES: Installation and connecting battery and servos SPECS: Channels: 2 Receiving Frequencies: 2.403 - 2.480GHz Modulation: FHSS spread spectrum Input Power Requirement: Four "AA" alkaline, NiCd or NiMH cells (4.0 - 6.0V) Dimensions: 1.77 x 0.98 x 0.5" (45 x 25 x 13mm) Weight: 0.25 oz (7g) Antenna: Internal jxs 6/10/09 ir/jxs updt jxs 03/03/10