Ping Sleeve 4UT 4HY 3UT 3HY Fujikura MCI 100 Flex: X Used with a G430 hybrid 3U. For hard hitters. Sleeve has scratches. Please check the photos. Innovative iron shaft that balances "flex" and "operability." MCT® (Metal Composite Technology) achieves the optimal balance between "flex" and "operability." Because of the "flex" unique to carbon, it's easy to pick up the ball and apply spin. Furthermore, optimizing the center of gravity allows for various shot types, enabling you to accurately target the pin. This is an innovative shaft for irons.