South Africa. (Great Britain). 1933. Air Mail envelope addressed to South Africa bearing Great Britain SG 429, 1s brown tied by London/ Air Mail double ring, underpaid with framed instructional 'More To Pay/ Veer Te Betalen/Above 1/2 Oz' and bearing South Africa postage dues SG D21, 6d black and slate (block of four) tied by Johannesburg date stamp.