This is a holder for a Half Bridge Load Sensor (https://www.sparkfun.com/products/10245, Cheap on ebay too).
Used in scales to allow the sensor to flex and move while supporting the sensor. This mount assumes you will use some glue or double side tape to keep them in place while moving it around. It has four 2.5mm holes for screwing the holder into the base but can also just glue it or tape it.
I'm using this with a Load Sensor Combinator (not needed, but makes it dead simple)
I am also using a Load Cell Amplifier (Amazon/ebay has HX711 chips too)
This piece has a lot of flexibility in terms of print settings. I did these at 50% infill but 25% should work as well.