The Mansfield genuine right hand 40 chrome is designed to fit the Mansfield models 11, 21, 26, 125, 159, 160, 165, 170, 171, 175, 180, 181, and 190. When facing the toilet this lever would be located on the right side of the tank. The lever comes complete with the reverse threaded nut that secures the lever to the tank. Since the nut is reverse thread it is left to tighten, and right to loosen.