1933 taxed advertising envelope. Franked on the reverse 5c, 20c & 10c adhesives tied 'KISUMU' c.d.s. '23 MY 33' On arrival in Mombasa four line Unpaid Postage Due cachet applied partly overstamped single 10c and a vertical pair 30c postage dues paying the 70ct charge tied 'MOMBASA' cancellation.