Booster Plug - What's Actually Inside

[Snowbird]

For 5v I have several pickaxe based projects on my boat that have worked fine for a few years using just lm7805 regulators with a couple on capacitors either side and a capacitor on the power in of each chip used to decouple, boat has 2 alternators,2 channel solar controller, and shore power battery charger so plenty mess with voltage, load wise both fridge and water pump make lights flicker.

Only thing missing is ignition coils to screw things up.