Altra Arrows Micro Insert Tool Silver. Made of 303 stainless steel these tools along with the insert weights allow for arrow weight customization which affects F.O.C. and allows you to fine tune your arrow?s total weight and improve down range accuracy depending on your specific bow setup. Specifications for Altra Arrows Micro Insert Tool: Manufacturer: Altra Arrows Color: Silver Features of Altra Arrows Micro Insert Tool: Comes in 12 pk QTY Used for all 166 arrows/components Package Contents: Altra Arrows Micro Insert Tool Altra Arrows AA-AC-00013: Micro Insert Tool Silver