‘Battle of Britain’ R.A.F. Biggin Hill First Day Cover, 18 September 1965, bearing the signatures of six ‘Battle of Britain’ personalities and aces: “Don” Kingaby, “Al” Deere, “Johnnie” Johnson, “Pete” Brothers, “Jimmy” Rankin and Brian Kingcome, the envelope bears the 1/3, 9d and six 4d ‘Battle of Britain’ postage stamps, good condition £30-50