Masonry screws

摘要

A masonry screw has a shank (14) having a leading end (16), a trailing end (18) and a longitudinal axis (20) and a thread (22) winding around the shank. The thread has a leading flank (24) and a trailing flank (26). Between an adjacent leading flank (24) and trailing flank (26) the shank has a non-uniform diameter to define a 5 depression (28) between those adjacent leading and trailing flanks. The depression has a first inclined face (42) that faces the trailing end (18). (Figure 1) P-AU-CDIY1175#PFI 39 28 26 22 4 4 4 2 224 320 '20