Super simple and functional spinning top, designed to fit a 9.5mm steel ball inside, the ball is coming from a spray can ( is one of the two ball contained in the can to mix the pigment with the solvent). You can use any other stell ball coming from bearing or anything else, just push it in the bottom hole and that's it! Print as many as you can for Christmas and give some to your best friends!! Super easy to print, I used 2 perimeters, 2 bottoms, 4 tops, infill 20% PLA. Use the cooling for the upper column, otherwise is gonna melt while printing!