Size - 24pcs mini chainsaw chain sharpener, 5/32" 4mm diameter, 20mm grinding head length, 3mm shank dia. Material - Diamond coated steel, high hardness and durable, excellent grinding effect with long service life, not easy to wear off. Application - These grinding heads are good for chainsaw teeth sharpening, also for metal surface polishing, wood and jade shaping, electric saws, glass, steel, and more. Feature - The chain grinding bits are easy to install, used with an electric grinder to easily sharpen your saw chain. Note - With finely and evenly diamond grains on the drill bit, the chainsaw grinding file is also suitable for high-precision work.