Summary

This is a simple bezel which can be used to mount a 0.91" OLED 128x32 display module on a panel. It's intended to be used with two M3 screws direct into the plastic through the panel from the rear. The mounting holes are 46mm apart and 4mm deep. The overall size is 54x20x5mm. Note that the OLED is not symmetrical, so it only fits the opening in one orientation (should be obvious when you try it).

The part I used was described as "I2C OLED Display Module I2C Screen Tiny Module 0.91 Inch Blue 128X32 DC 3.3V to 5V"