BULL’S Challenger Darts – Steel Tip – 90% Tungsten – Arno Merk – 22g. The Arno Merk Challenger Steel Darts combine precision engineering with a distinctive design, perfectly suited to Arno Merk’s playing style. Made from high-quality 90% tungsten and available in 22g, these darts offer a professional setup with both style and substance. The barrel features a visually striking separation between two grip zones. The front section is relatively smooth,highlighted by a sleek black coating and finely engraved symbols that give the dart a refined, individual look. At the center of the barrel, you’ll find the classic BULL’S logo, with Arno Merk’s personal logo engraved on the opposite side adding a unique and personal touch.