A set of different height unit bins to dry fit and plan layouts. The label with the dimensions in gridfinity units is printed on the floor of the bin for easy reference. Gridfinity units are 42 mm in X and Y, and 7 mm in Z (not accounting for the bin base offset which is around 4 mm). This means a 1x2x3 bin would be 42mmx84mmx(21mm+4mm). See https://gridfinity.xyz/specification/ for detailed specs.