Hot Launch C522 Irons The Competition Spec Hot Launch C522 irons are maximum distance and forgiveness irons in a traditional cavity back design. The Hot Launch C522 Irons are made with extremely soft 431 stainless steel, providing the optimal feel for players of all levels. FEATURES VIBRCOR TECHNOLOGY Internal VibRCor TPU delivers REMARKABLE FEEL AND ADDED POWER EXPANDED 360* UNDERCUT CAVITY Expanded undercut cavity lowers the CG for increased LAUNCH AND FORGIVENESS WIDE SOLE DESIGN Creates cons