A comprehensive set of 12 balls. Includes one each of 25mm diameter drilled aluminum, copper, steel, and wood balls, two each of 25mm drilled brass balls, two each of solid steel balls (one plain and one with suspension lugs), 38mm diameter brass, steel, and copper balls with hooks, and a 38mm cork ball. All drilled balls feature 3mm countersunk holes so pendulum cord knots can be recessed. Packed in a plastic storage box.