Abstract: A visible erosion indicator is provided to determine the condition of contacts inside a vacuum interrupter. The visual indicator is located on a portion of an extension of the moveable contact drive stem which is a threaded stud. The indicator is formed from a flexible member that is screwed onto the stud until a given extent of the flexible member protrudes beyond the bottom pan of the circuit breaker, that the moveable contact stem traverses during opening and closure of the internal contacts within the vacuum interrupter. The extension of the wear indicator is measured with the circuit breaker in the closed position to provide an accurate measure of contact wear. The flexible property of the wear indicator enables it to clear obstructions as the breaker drawer is moved within the breaker enclosure.