Here are 3 different sizes of furniture feet. They have a non-slip pattern on the top. I tested these against normal, smooth finished feet and there is a noticeable difference. You can use a M3 washer for extra strenght in the top hole (diameter 9mm). The bottom hole is 3mm in diameter. All feet share the same base diameter of 24 mm and the same holes.
Height:
Small: 10mm
Mid: 15mm
Big: 20mm