This is a great usage for a US First Day Cover of US 792, the 3c Navy stamp of Feb 18, 1937, postmarked at DC, and addressed to

Lt Col Edward Roth, Jr., at the HQ Panama Canal Department in Quarry Heights, Canal Zone. Roth later served stateside in \WW2/

Bicolor engraved Grimsland cachet honoring Adminrals Farragut and Porter. Lower left corner bends that might be flattened out, otherwise F/VF; the usage still makes this quite collectible. High bidder pays $1.50 shipping within the US; $2 international. We combine shipping so buy other of our items!