Description No machine component seems more elementary than a knob bolt. But in fact, there are many possible configurations for this simple part, and choosing the right type is key to the optimal function of the machine. These types of knob bolts are easy to grip and work well in slippery environments. It can be installed or removed freely without any other tools, install or remove it by directly turning the screw. Features -Color: Black. -Material: Plastic, stainless steel. -Size: 3.30X2.70X0.50cm/1.30X1.06X0.20in - Made of plastic and stainless steel for stronger rust resistance, more durable, more . - It is rust-proof and , durable and hard to break, which prolongs the service life of the product. - These screw knob replacements are easy to tighten/loosen and no extra tool required. - Unique shaped design with a comfortable grip. The fully threaded design is easy to install, disassemble and adjust. - Fit for mechanical equipment, electronic equipment, lathes, furniture decoration, construction and other related industries. Package list: 10 x Thumb Screws