Check the listing for details. Knurled Thumb Nuts, 30Pcs M4 x 12 x 8mm Carbon Steel Knurled Nut, Silver. Condition: New. Listed at 11.15 USD. Description:Material: The knurled thumb nut is made of carbon steel materials and treated with nickel plated for high hardness, durability, wear resistance, and sturdy. Stable performance can be maintained both in the working environment and in long-term use.Advantages: The head has a knurled design to increase friction, and it is easy to install and remove by hand without any tools. The thread is deep, the tooth pitch is uniform, and the fastening force is good.Application: These knurled thumb nuts are widely used in the machinery industry, furniture fastening, 3D printing parts, etc. Great for items that need quick adjustments. Use them to replace old ones, or just store them for your next install.Specification:Material: Carbon Steel Color: SilverSurface: Nickel PlatedThread Size: M4-0.7Total Size: 12 x 8mm/0.47" x 0.