Description The CMI Archery 4MM SS HIT Insert is a precision stainless steel insert designed to improve arrow durability, balance, and overall performance in micro-diameter arrow systems. Built for 4mm arrow shafts, this HIT (Hidden Insert Technology) design installs inside the shaft for a clean, streamlined profile that enhances arrow flight and broadhead alignment. The stainless steel construction adds front-of-center (FOC) weight for increased penetration and impact performance, making it an ideal upgrade for bowhunters and target archers seeking consistent accuracy and long-lasting durability. Specs Weight 25 grain Material Heat-treated 416 stainless steel