Abstract: A cleaning shoe of an agricultural combine having a chaffer screen and sieve screen which are provided with readily replaceable louvers. Both the chaffer and sieve have rectangular frames across which extend laterally arranged louvers. The louvers are held in place by a readily removable adjustment bar which is used for adjusting the opening side defined by the louvers. The adjustment bar is slidably mounted in a U-shaped member having inwardly turned lips that together with a retainer strip and a spring lock the adjustment bar into the frame thereby holding the louvers in place. By removing the retainer strip and spring, the adjustment bar can be removed and the louver replaced.