DescriptionKeychain identification tag: United States Testing Co., Inc. 1415 Park Avenue, Hoboken, N.J. 07030. No date, circa 1970-1990. Brass double-sided medallion with relief lettering and art, 1-1/4" diameter plus ring loop. With: 1/2" diameter split ring for keychain attachment. The front has the company name and insignia logo. Back has text: Deposit in any mailbox [stamped]1090 1415 Park Ave. Hoboken, N.J. 07030 Return Postage Guaranteed.