Flexible mount for the Digital Multimeter to keep the hands free. It is a holster and I use it with my mount system: https://www.thingiverse.com/thing:4110316

But it can also combined with any GoPro compatible mounting parts.

I've designed it for this Multimeter: https://www.banggood.com/MUSTOOL-MT8206-2-in-1-Intelligent-Digital-Oscilloscope-Multimeter-with-Analog-Bar-Graph-p-1331666.html?rmmds=search&cur_warehouse=UK

It can be used for similar sized devices.