This is a keystone blank insert for a keystone jack in a wall plate or keystone panel.  There are many others available; this one prints a little uniquely and I use it as a base model for specialized adapters.

My printers have 0.6mm nozzles, so I print these using 0.4mm layer height and 100% infill. For smaller nozzles a 0.3mm or 0.2mm layer height will likely work better. There are some overhangs in the model, but they seem to print just fine for me without any support material using standard bridge settings. I typically use PETG filament because it can handle flex on the latch component better than other materials like PLA.

The model includes a “support tab” between the keystone latch and the print surface; after printing you can cut off or break off this tab to expose the latch.  The layer lines aren't ideal for the latch – it can break if over-stressed, but after printing and testing dozens of these I've had only one latch break (when I attempted to install it incorrectly).

Other keystone adapters:

  [https://www.printables.com/model/587813-keystone-adapter-for-powerpole-connectors](https://www.printables.com/model/587813-keystone-adapter-for-powerpole-connectors)