From 17 February 2009 1st and 2nd class Machin Definitives and higher-priced 'make-up' values at 50p and £1 were produced as self-adhesive stamps with enhanced security features including semi-circular slits and an iridescent overprint.
These initiatives are part of the on-going development of security features for Stamps. The slits are designed to inhibit the removal of these Stamps for fraudulent sale and re-use. The overprint features the words 'Royal Mail' in a pattern reminiscent of security features on banknotes.
This is the 2nd class Large Letter from Business Sheets, reprinted in 2010 with year code MA10. These stamps from Business Sheets have differences in the ROYAL MAIL overprint to indicate their source, the coding has changed to ROYAL MBIL for this reprint..
These were available in 2012/13 and sold out quite quickly. Further supplies did not appear in post offices, but a small supply has been found and is now available. Order now as this cannot last!