These screws have a low profile head that is just 1.5mm thick. They are perfect for use with all kinds of brackets and plates in any projects that use 20mm aluminum extrusions. The 25mm and 30mm screws work well with V Wheels to create simple linear motion systems. Build CNC routers, 3D printers, CNC laser cutters, CNC plasma cutters, robotics projects, 3D carvers, machine guards, workstations, etc.