1, Automatic Screw Dispenser 2. One machine fit one screw size, which make the Screw Supplier stable and easy to use. Features:Models: 514, 517 ... circuit, energy saving; 4,One machine fit one screw size, which make the Screw Supplier stable and easy to use5,Various models ... Φ2.6 Φ3.0Φ4.0 Stable and Easy Use Automatic Screw supplier