Check the listing for details. 6Pcs Knurled Thumb Nuts M4 Brass Nut High Head Through Hole for 3D Printer Part. Condition: New. Listed at 11.98 USD. Description: [Material] Our knurled thumb nuts are made of brass, with nickel plated in the surface, high-hardness, durable, wear-resistant, sturdy, not easy to rust or fade, with a flat head and round knurled body, which can be used for a long time. [Advantage] Knurled thumb nuts are designed with clean, compact, and accurate thread, which makes it not easy to be out of shape or slide in the process of rolling. [Easy to Use] Our adjusting nuts are designed with a knurled surface and clear slotted head, which can be easily tightened, installed, and removed by hand. No tools are required. [Wide Applications] These round knob fasteners can be widely used in the machinery industry, furniture fastening, 3D printer beds, and other electrical or industrial products.