Arcade Otaku - アーケード オタク

Is there a particular LCD readout voltmeter that people recommend to use? I'd like one that gives me a continuous reading on my +5 inside an NAC, to ensure it's giving enough juice to the various boards I use. I vaguely recall seeing a lovely red LCD readout in a pic on this forum.

Anyhow, any recommendations welcome. I've seen this kind of thing on eBay, but I'm not sure if that's the best solution...

https://www.ebay.com/itm/174294149116

That is a Negatron adapter, its aimed for jamma cabinets that don't have a negative 5 volt output rail on their PSU's, not your case if you have a NAC.