Material :rare earth magnet ( neodymium ) Grade:N35 Diameter:5mm Tolerance:+-0.03mm Function:educational toy Neocube is ... according customer request.size from 3mm to 30mm.grade from n35 to n42color:nickel,black nickel,silver,gold, red, green,blue ... 's packing is accepted. 5mm neocube, D5 buckyball, magnetic ball,N35 Neodymium, 216pcs/set