15s+5s 1920 Siam "Scout's Fund" Type II overprint, with 15s additional franking, on July 17, 1934 registered commercial cover from Bangkok P.O. No. 105 to Hong Kong.  The 30s total franking paid the registered, single weight foreign letter rate (15s + 15s), following the October 1925 foreign rate reduction.  Messrs. Graca & Co. was a well known stamp dealership in Hong Kong.  An example of late usage (14 years after issue) for face value postage of a low value "Scout's Fund" semipostal stamp on a commercial mailing from one stamp dealer (or collector) to another stamp dealer.