Here are a couple gray Westinghouse 9kv Autovalve arrestors on the old 100hz signal building at the former PRR Conestoga Substation. This sub steps up the 25hz catenary power generated at the Safe Harbor Dam to 138kv. The signal building was used up until the the late 2000s when the old PRR signals were replaced along the adjacent port road line, and the 6.9kv 100hz power was no longer needed. The multiparts are Ohio Brass M-2303s and the suspensions are PRR Locke bells.