Check the listing for details. Knurled Clamping Knobs, M6 x 25mm Thread 21mm Head, Thumb Screw Bolt, 4-Pieces. Condition: New. Listed at 11.78 USD. Attributes:* Male Thread Size: M6 (1mm Pitch)* Thread Length: 25mm / 0.98"* Head Diameter: 21mm / 0.83"* Total Length: 38mm / 1.5"* Material: Plated Steel, Thermoset Plastic* Color: Black, Silver ToneWhat Is Included:* 4 Pieces x Knurled Clamping KnobsApplications & Features:--- The knurled clamping knobs are designed to provide a secure grip and quick adjustment, making it suitable for a variety of industrial applications. Widely used in lathes, drill presses, sawing machines, milling machine fixtures, packaging machinery, printing equipment, woodworking machinery, mechanical equipment, instrument equipment, food and industrial equipment.--- The knurled surface on knobs provides a non-slip grip, even with gloves or wet hands.