Walkera DEVO4 Controller for QR W100S Quadcopter
The Walkera DEVO4 is a great option for flying your QR W100S Quadcopter.

TTX491 4Ch 2.4GHz SLT Surface TX Only Mode 2
This is the Tactic TTX491 2.4GHz 4-Channel SLT Surface Transmitter.

DX4C DSMR 4CH Tx w/SR410

DX4C DSMR 4-Channel AVC Transmitter with SRS4210

Spektrum DX4S DSMR 4-Channel AVC Radio with SRS4210 & SR410
The DX4S DSMR surface radio system offers an impressive list of programming features plus the amazing stability of AVC (Active Vehicle Controlª) technology.

Futaba 4YF 4-Channel 2.4GHz FHSS Sport Radio System - No Servos
Futaba quality, FHSS technology and an economical price make the 4YF 2.4GHz FHSS radio an excellent choice for cost-conscious modelers wanting an interference-free spread spectrum system for sport flying.

Futaba 75Mhz 4YF Radio System Package - No Servos
This is the Futaba 4YF 4-Channel FM Radio System with the R168DF Receiver. A great, budget-priced four channel 75Mhz radio!