4x Power Functions to Powered Up/Control + Adapter - SBrick
10V 700mA 0.7A Universal AC DC Adapter Charger For Lego Mindstorms EV3 NXT 45517 Power Supply, World Wide Input Voltage 100-240VAC 50/60Hz. OVP, OCP, SCP.., By Brand Magnetbest - Walmart.com
External power supply for NXT®
How to Hack a LEGO Power Functions Cable for Direct 9V Power - GeekDad
Custom LEGO Power Functions 9V Power Supply
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