Bidspirit auction | United States
United States - 1973, Progress in Electronics, 8c multicolored, tan and lilac colors omitted, full OG, NH, VF, C.v. $600 , Sc. #1501b
United States - 1973, Progress in Electronics, 8c multicolored, tan and lilac colors omitted, full OG, NH, VF, C.v. $600 , Sc. #1501b