Lower costs associated with rework, labor, safety, and maintenance with this 0.764 x 0.771 in Polypropylene Round Knob Assembly. Keep your machine operating its best with OEM parts. Parts are machine specific. Please check your machine model and serial number before ordering. Replaces 579013, 630437. Fits Tennant 1510, 1610, T2. Nobles Strive ReadySpace. 1 each