South Africa 1929 Airmails 1/- "Break in Bottom Frame" Block

1929 Airmails 1/- orange "Break in bottom frame under "U" of "LUGPOS" (SG 41var). VF/UM/M bottom marginal block of four, the margin with jubilee line & coloured dot for perforation alignment. Variety (which is UM) UHB 21 V1 R12/5 shown clearly on bottom right corner stamp. Fresh.