Sandy Spring, MD, REGISTERED handstamp
Manufactured by the Baumgarten Company of Washington, D.C., this device has a wooden handle attached to a cast metal socket. A foam rubber cushion and rubber marking die has two concentric circles, lettering between them, and center slots for month, date, and year. The rubber cushion and marking die are joined by rubber cement. This assembly is inserted into the handle socket.
It functioned as a backstamp on registered mail matter as well as stamping along the edges of package seams to reduce undetected tampering. Its imprint was also applied to receipts and official reports pertaining to registered mail. Ordinarily, these imprints were made using red ink, contributing to the nickname 'reds' for registered mail.