1949 incoming British taxed air mail: Sept 1949 airmailed small commercial cover from LONDON to TEL AVIV, endorsed "by Air Mail" & franked 3d using business meter cancel, but taxed by the Foreign Section of the London head post office using tall mute hexigonal serifed-T cachet with boxed F.S initials below (probably Type FS-2 per the Postage Due Mail study group) & "42" in manuscript per value of period French Gold Centimes, which converted to 43pr locally in Israel, which was charged using 1x 3pr & 2x 20pr franks (Ba #PD1/4; note ink anomaly on right frank) of the 1st postage dues series and applied on 2-10-1949 (per Hebrew date of the unclear postmark): as the cover was unsealed (full gum intact), it was probably supposed to be printed matter mail (whose 1948-1952 period airmail rate to Israel was 3d for half an ounce), and this borne out by the business meter franking - but the cover was not so marked, so charged double the 3d deficiency for the standard period airmail letter rate of 6d for half an ounce. Certified Ising BPP (Israeli philately expertizer, Wolf Ising - Bund Philatelitische Prufer, of Ellerbek Germany) on back corner.