Sterling Siren Company (by Sentry,) 5V and Federal Signal STH-10 - Daugherty Township Fire Co. STH is rapidly losing horns almost every 2 years, one was put on the trailer. FD plans to replace the STH with the 5V when it’s fixed, STH will still stay on the roof when replaced. 5V badge says, “Sterling Fire Siren Company, (By Sentry,)” meaning that it could either be called a Sterling 5V or a Sentry 5V. Submitted by The Railcat.