Specifically designed to fit the carbon express maxima triad arrow this two- part insert system utilizes a stainless steel insert that threads to an aluminum exterior threaded collar. Strength and concentricity are maximized to provide optimal arrow flight and extreme durability that perfectly align with the overall benefits of this carbon express’ exclusive tri-spine micro diameter triad arrow system. At 94 grains this system generates excellent foc for extreme penetration. Available to fit all three spines offered.