Square head 12 - protrusion 18 mm - use tapered punch BOUT1.
For competition, soft and slippery ground. Shoe thickness 10 mm. Square head 12 mm wrench, protrusion : 18 mm out of the shoe. Tapered shank with big diameter 9.5 mm. Drill Ø 8.5 mm and use tapered punch ref. BOUT1. Weight 25 g.