114 defines recesses the recesses include deep recess portion 173 and shallow recess portion 174 underside 170 has upper ceiling 177 a lower ceiling 177 b and edge 181 the recesses receive middle portion 132 and lower portion 130 of shank 120 gear 160 a portion of spool 162 and biasing member 164 upper ceiling 177 a defines deep recess portion 173 and lower ceiling 177 b defines shallow recess portion 174 deep recess portion 173 has main recess portion 173 a and side recess portions 173 b c edge 181 deep recess wall 183 and shallow recess wall 185 define the shape of deep recess portion 173 and shallow recess portion 74 deep recess portion 173 is shaped conformingly to and receives baseplate 112 the plane formed by edge 181 of base housing 114 defines the lower planar boundary of underside 170 extending downward from lower ceiling 177 b are recess posts 140 recess posts 140 generally are integral with upper ceiling 177 a and lower ceiling 177 b and do not extend beyond the plane formed by edge 181 of base housing 114 recess posts 140 have main support sections 142 and support surfaces 143 support surfaces 143 of recess posts 140 are substantially coplanar support posts 140 a b proximal to spool post 190 may have tip sections 144 when baseplate 112 is situated on recess posts 140 in deep recess.