Made of 1025 carbon steel, they undergo a multi-step forging process to ensure precise shaping for further enhanced feel and responsiveness. A horizontally milled channel in the cavity separates mass on the vertical axis for precise inertia and trajectory control. Inspired by P·730 irons, the RORS∙PROTO 7-iron and 8-iron have a thinner top line, which is Rory’s visual preference. Instead of the MX9 grooves found in P·730, RORS∙PROTO irons have TW2 grooves which are used in P·7TW irons.