This is an England OHMS, or ON HIS MAJESTY'S SERVICE Admiralty Cover sent to Isleworth, Middleton, England on 9/30/1897.

There are a couple of things that make this little guy really special and RARE.  First is the BLUE ANCHOR OF ACCOUNTANT GENERAL OF THE NAVY FOR NAVAL PENINSULA OF ISLEWORTH CIRCLE SEAL on the bottom left side of the front of the cover.  It also has a LONDON OFFICIAL PAID CDS in RED.

The cover itself is in Very Fine condition.