Ultra-solid ball knob with a Shiny finish, suitable for general application,such as lawn mowers, exercise equipment, machinery, valves, spigots, etc. Product Name: Ball Knob Mounting Type: Female Thread Thread Depth: About 21mm/ 0.83 inch Mounting Thread Size: M8 Spherical Diameter: 30mm/ 1.18 inch Material: Thermoset Rim Style: Smooth Package Content: 4 Pcs x Ball Knob