Features: 100% brand new and high quality. Made of zinc plated carbon steel, these thumb screws are sturdy and durable. Thumb screws with flat knurled head can provide extra grip for manual tightening. Thumb screws are designed to be tightened and loosened by hand,easier to drive manually. Widely used for electric appliance, tools, cars where screws need to be tighten and loosen frequently. Specification: Material: Zinc plated carbon steel Size(D*L, diameter*length Optional): M4*6 D=4mm L=6mm M4*8 D=4mm L=8mm M4*10 D=4mm L=10mm M4*12 D=4mm L=12mm M4*14 D=4mm L=14mm M4*16 D=4mm L=16mm M4*18 D=4mm L=18mm M4*20 D=4mm L=20mm M4*25 D=4mm L=25mm M4*30 D=4mm L=30mm M4*35 D=4mm L=35mm M4*40 D=4mm L=40mm Quantity: 5pcs Weight: 20g~32g / 0.7oz~1.1oz (approx.) Package list: 5 * Screws1100% brand new and high quality. 2Made of zinc plated carbon steel, these thumb screws are sturdy and durable. 3Thumb screws with flat knurled head can provide extra grip for manual tightening. 4Thumb screws are designed to be tightened and loosened by hand,easier to drive manually. 5Widely used for electric appliance, tools, cars where screws need to be tighten and loosen frequently.