General description Manufactured from high-quality chrome molybdenum steel, the Kennedy 1" Square Drive x 100mm (4") Impact External Bar features a black oxidized finish with permanent laser-etched markings for durability and easy identification. Technical specifications Accessory Type: Extension Bar Drive Size: 1 inch Finish/Coating: Black Oxide Material: Chrome Molybdenum Overall Length: 100mm Size System: Metric and Imperial Other information