The Luxilon Alu Power Vibe is the first string blended with dampening material and reduces vibrations by 17% compared to undampened string. Makes for a softened feel upon contact with the ball. The Luxilon Alu Power Vibe reduces vibrations throughout the entire string bed for more comfortable feel regardless of contact point. Recommended for competitive players looking for the performance of a polyester string. This is a polyester string.