Aiming of Zetro Quad is purely the improvement of the ability of topspin.
Zylon fiber which directly placed under top layers increases the ability of grabbing ball.
Soft carbon fiber under middle layers adjusts overall performance, and at the same time reduces the unnatural feel which is the shortcoming of Zylon fiber.
Top layer of selected Kiso Hinoki guarantees comfortable feel.
The result is great ability of topspin.
Making heavy topspin is effortless, and even secure.