Rory McIlroy is using a prototype Mitsubishi Rayon shaft this week at the U.S. Open. (Getty Images)
By Jonathan Wall, PGATOUR.COM Equipment Insider
After doing some shaft testing at home in the weeks leading
up to the U.S. Open, Rory McIlroy switched to a Mitsubishi Rayon prototype
that's similar in look to the company's Kuro Kage Silver shaft.
McIlroy had been using a Mitsubishi Rayon Diamana Prototype 70X in his 10.5-degree Nike VR_S Covert Tour driver but decided to change shafts because he liked the higher ball flight and tighter shot dispersion.
According to Mitsubishi Rayon reps, the shaft McIlroy's playing is one of several prototypes the company has been working on over the past year as it develops the next generation of KURO KAGE profiles.
While the prototype has the same color scheme and profile as the Kuro Kage Silver that's currently available at retail — stiff tip and mid section, and softer butt section — McIlroy's shaft has TiNi Fiber Technology, a unique Titanium and Nickel alloy that was added to reinforce the graphite.
When stressed, the fiber deforms and then recovers immediately to its original shape. TiNi was used in the tip section of the company's Bassara G-Series and W-Series to promote launch and clubhead speed through impact.