Mac Mini Upgrade

16GB max and your best bet, is to order the correct spec'ed 1600MHz DDR3L SO-DIMM PC12800 204 Pin modules directly from either OWC macsales or Crucial.

https://eshop.macsales.com/shop/mac-mini/

https://www.crucial.com/usa/en/compatible-upgrade-for/Apple/mac-mini

That is correct.

1. All Mac's are very sensitive to the RAM spec's.
2. The Late 2012 Mac Mini has a DDR3 controller and memory slots.
3. DDR3 and DDR4 modules have different notch locations and are not interchanged.

see > https://www.quora.com/What-is-the-difference-between-DDR3-RAM-DDR4-RAM

FYI: the correct abbreviations: Gigabyte is GB, not gb. g=grams, or the acceleration of gravity, b=bit, and Gigahertz is GHz.