1st class red Security Machin forgery.
One of several types which have been produced.
This type has coding MTIL M13L for a booklet of 12
The background is dull, but the text is clearer with only the letter M at top right
The phosphor does not react to UV light
NB Some of these forgeries are difficult to distinguish from each other, and I may have listed as different stamps which are in fact the same type as identified by the Modern British Philatelic Circle or others. If this proves to be the case and you wish to return a purchase, please email first per our Terms and Conditions, so that we can discuss.