30.br2
Centre slightly recessed, heavy pointed teeth | 30.br3
Centre not recessed, pointed teeth, single-tapped | 30.br4
Centre not recessed, correct teeth, double-tapped | 30.br4a
Centre recessed, double-tapped |
30.br4b
Deeply recessed (> tooth size), double-tapped | 30.br
Flats on teeth, double-tapped post-war stamping | 30.br1
Flats on teeth, teeth slightly narrower |