In {HEAD ~ accordance} with {TAIL ~ another feature} of the present invention, the abutting edges may also have toothed portions defined by straight lines, for example, toothed portions formed by triangles, rectangles or trapezoids 
with
In { HEAD ~ accordance } with { TAIL ~ another feature } of the present invention , the abutting edges may also have toothed portions defined by straight lines , for example , toothed portions formed by triangles , rectangles or trapezoids
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