a vintage US cover advertising S.C. Sleeper, Manufacturer and Dealer of Bricks in Plaistow, NH.
the color is "brick red" for 

(since most of the collection that this cover came from was the 1880's, we are surmising this was the decade)

fancy cancel: bullseye with "3"

3.25" x 5.5"

trimmed, slit open at side

see images

This is one of hundreds of 19th C. advertising covers and fancy cancel covers we will be selling.from an extensive collection.