Service Entrance Watertight Connector 1″ with 0.406″ Opening
https://nsiindustries.com/product/service-entrance-watertight-connector-1-with-0-406-opening/
The Bridgeport 1″ Zinc Die Cast Service Entrance Watertight Connector with 0.406″ Opening securely creates a watertight seal around service entrance cable. The compression connection secures the entrance cable.