North Hills, Calif.-based Moore Industries is celebrating its 40th anniversary this year. To honor its history, the instrument manufacturer is seeking the oldest of its products that are still in service.

The company is offering $500 in merchandise to the top three companies who can prove they are still using the oldest Moore Industries products. To submit an entry for the Oldest Moore Industries Product, send an e-mail oldestmiiproduct@miinet.com by August 1.