S.Bus Decoder 8-PortThe SBD 2 is a converter for using conventional servos (other than S. BUS servo) with the S. BUS S. BUS2 system. The SBD 2 connects to the receiver output of a S. BUS S. BUS2 system and eight servos can be used. SBD 2 can change the output CH from 9 groups select by rotary switch. SBD 2 can use EXT battery (for servos). Applicable receiver: S. BUS S. BUS2 system receiver only Dimensions: 29. 6 x 39. 3 x 15. 8 mm Weight: 14. 2 g Power requirement: 4.