inside the mortise of the door 12 from a closed position to an open position as shown in fig2 a lever stop plate 32 is mounted to the square spindle 30 and connected to the inside lever handle 28 the lever stop plate 32 has a curved rack 34 with eight teeth 36 a circular spur gear 38 has an opening 39 at the center thereof and twelve spaced apart spurs 40 outwardly extending with respect to an axis going through the opening 39 the spur gear 38 has its spurs 40 meshed with the teeth 36 of the curved rack 34 rotation of the spur gear 38 in the direction indicated by the arrow a moves the lever stop plate 32 from the closed position shown in fig2 to an open position in the direction shown by the arrow b as shown in fig3 the spur gear 38 has a front surface 42 which defines an annular recess 44 about the opening 39 an abutment 46 extends radially inwardly in the recess 44 for purposes to be later explained as seen in fig2 the opening 39 of the spur gear 38 receives a tailpiece 60 extending from a rotatable cylinder lock 62 fig1 for movement therewith the cylinder lock 62 is actuatable with a key 64 fig1 insertable through an opening 66 in the outside housing 20 the key rotates u2154 of a turn for retracting the latch bolt 31 the cylinder lock 62 may be a 6 pin u201c key in knob u201d such as the cylinder lock from lori lock and rocky mount and the key 64 may be a lockwood 1004 reverse mushroom pins not shown may be used for at least three.