1st class rayal mail submarine stamp

A rare and unique item!

The 1st Class Royal Mail submarine stamp you're referring to is likely the "Submarine" stamp issued by Royal Mail in 2012 to commemorate the 100th anniversary of the Royal Navy's Submarine Service.

Here are some details about this stamp:

• Issue date: April 2012
• Denomination: 1st Class (64p)
• Design: The stamp features a colorful illustration of a Royal Navy submarine, with a diver in the foreground and a submarine in the background.
• Printing: The stamp was printed by International Security Printers using a combination of offset lithography and intaglio printing.
• Perforation: The stamp has a perforation of 14.5 x 14.5 guillotine.
• Sheet composition: The stamp was issued in a sheet of 10 stamps, with a gummed strip at the top and a label at the bottom.
• First day cover: A special first day cover was issued featuring the stamp and a commemorative postmark.

This stamp is a unique and interesting item, especially for collectors of Royal Mail stamps, submarines, or the Royal Navy. If you have this stamp in your collection, consider yourself lucky!