Ping G5 Irons. A deeper, parallel cavity design widens the sole and expands the perimeter weighting to make the G5 the most forgiving Ping iron to date. The larger head, cavity design and sole width provide higher launching, more consistent shots. The 17-4 stainless steel heads are investment cast and heat treated at Karsten Manufacturing's foundry in Phoenix, Arizona. The Ping G5 iron's feel is improved through a larger, thinner Custom Tuning Port (CTP). The expanded port is positioned closer to the face to ensure consistency and a solid, pleasing feel. The lead-edge radius is designed for improved ground impact and more solid ball contact.