Features Good material: Mainly made of high quality alloy steel material, waterproof and rust-proof, also excellent durable for long time use. RELIABLE WORK Works perfectly with timing belt, the synchronous wheel allows stable transmission in linear motion and positioning. Wide Application Widely used in 3D printers, CNC, milling machines, gear forming machines, drilling machines, CNC lathes, etc. BETTER DESIGN This high precision 80T GT2 synchronous pulley with 5mm inner diameter is suitable for timing belts with 6mm width. Easy Installation Due to the compact size and light weight, the installation can be completed quickly with an Allen key and an M4 screw hole. Specification: Item Type:Synchronous Wheel Material: alloy steel. Pitch: approx. Approx. 2 mm / 0.08 inches. Number of teeth: 80T. Outer diameter: approx. 55 mm / 2.17 inches. Flange:Double Flange Mounting: 2 x M4. Pulley timing diameter: approx. 5 mm / 0.2 inches. Applicable belt width: approx. 6 mm / 0.24 inches. Package list: 1 x synchronous wheel. 1 x hex key Package List 1 x Synchronous Wheel 1 x Hex Wrench