It offers us a large number of bases with various reproductions.
The filler piece is a wedge that fits between our bases and allows us to create a new base of different sizes and shapes.
This piece adds good stability and union between the bases.
Eliminate and adjust the possible excess with a blade.
Remember that we can magnetize our bases by adding a piece of metal or magnet inside our mold and pouring the reproduction material, this avoids having to drill or hole the penalty later.