The October Mountain Accu-Arrow Digital Archery Scale is a digital archery scale designed to weigh in grains only. Includes arrow retainer. Measures with +-0.2 grain accuracy.This scale is awesome if you are trying out a heavier arrow setup and want to mess with the grains in your arrow. FeaturesHigh capacity, high accuracy digital scaleArrow retainer includedWeighs in. grains only3086 grain max x 0.2 grain accuracy4 3/4inLX 3 1/4inW X 15/16in H