This shaft was developed by a team that conducts cutting-edge swing analysis and theory, as well as training and fitting. This shaft was completed after repeated testing. 

Conventional shafts for athletes tend to favor a "do nothing" behavior and tend to increase rigidity. However, after analyzing miss shots with such shafts, we noticed that the timing is off because of the force generated on the turn from the top, resulting in a miss shot that deviates from the swing plane and reduces distance and directional accuracy. 

The PROTO BI has a slight action point on the hand side, which makes it possible to feel the perfect pause on the turn.

This makes it easier to get the timing right and swing through from a smooth turn to the finish, which improves the meet rate and enhances control performance. 

The materials used are TORAYCAM40X, Toray's state-of-the-art high-compression strength, high modulus carbon fiber, and TORAYCAT1100G, a high modulus, high strength sheet, as well as a 50-ton sheet. The laminate with a higher ratio of high modulus than conventional shafts for athletes achieves the same hardness, but with lighter weight specifications to increase speed and reduce blurring. 

The sharp, exhilarating, and comfortable feeling of the shaft allows the player to increase their speed as they continue to use it. 

The exterior is a matte black finish.

The black matte finish creates a new world view of the Fire Express. This shaft is designed to meet all kinds of demands: to catch power, to keep up with speed, to fly, and to control the ball.

This is a shaft for top-level players and developing players who want to become top-level players.

Tip 8.55mm.

The frequency is based on a 200g head (including sleeve), 45.5 inches (60-degree measurement).

The vibration frequency may vary greatly depending on the depth of insertion of the hosel and other factors.