RioRand RR-PWM-15V Low Voltage Dc 1.8v 3v 5v 6v 12v Motor Speed Controller, 2A PWM - Amazon.com
KBVC-14 (H9053)- DC Drives, 90 VDC, Variable speed control for Permanent Magnet (PM), Shunt Wound and Universal (AC/DC) motors,Hi/Lo Converter 5-Channel with 12 Volt Trigger Output (Remote out),RioRand RR-PWM-15V Low Voltage Dc 1.8v 3v 5v 6v 12v Motor Speed Controller, 2A PWM - Amazon.com,Malekko Voltage Block (Black Panel Only)