The Size You Will Get Thread size: M8 x 20mm / 0.31'' x 0.79''(D x L), M8 Head Dia (Approx): 39mm / 1.53'', please check the thread you need before buying Size, male knob is ideal for DIY projects and home repairsQuick & Easy Installation No hardware required, this male threaded knobs adopts special star design, comfortable in hand, ergonomic, easy to turn with just your fingers, will not scratch your hand.Come together to diy and install these star knobs into your threaded holesHigh-Quality Material The screw is smooth and burr-free overall, comfortable to hold, the thread is deep and complete and clear, the force is even and not slippery, the stud is made of carbon steel, the surface of the screw is galvanized process, uniform plating, high hardness, durableRisk-Free Shopping If there are any quality problems with our products, please contact us via Amazon email as soon as possible. We will sincerely serve you within 29 hours and give you a satisfactory solution. Please rest assured to order, we wish you a happy shopping experienceWide Scope of Application M8 threaded knob Suitable for speaker stands, automotive, woodworking fixtures, industrial instruments and other machinery and equipment, workbenches or benches, is the best choice for clamping operations, industrial equipment, is your daily life to replace the tightening screw