12V Low noise DC Motor 146RPM w/Encoder - DFRobot

DFRobot 6V 160rpm Micro TT DC Geared Motor 0.2kg with 120:1 Gearbox Quadrature Encoder for arduino Mobile Robot Smart Car - AliExpress

12V Metal DC Gearmotor w/Encoder (131:1, 83RPM, 45Kg.cm) - DFRobot

12V 168P Gear Motor with Encoder - DFRobot

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12V 120 RPM DC Motor 64:1 - RobotShop

Buy DC Motor 122rpm w/Encoder 12V DF-FIT0403 DFRobot

HCR - Mobile Robot Platform (Support Kinect) - DFRobot

DFRobot 6V 160rpm Micro TT DC Geared Motor 0.2kg with 120:1 Gearbox Quadrature Encoder for arduino Mobile Robot Smart Car - AliExpress