Anet/Zonestar LCD 2004 Anti-rattle spacer.

thingiverse

The screen on these boards relies on tension from solder joints to the LCD between them to prevent rattling. As soon as the printer was reassembled, an annoying rattling developed. These spacers keep the rear of the LCD board from knocking against the backing board. The base is small, prints slowly and requires a brim. Some Z scaling may be necessary to match the solder joint on your display. Installing these spacers unnecessarily can actually cause problems. If the display isn't rattling, don't install them, because flexing the boards is likely how this problem developed in the first place.