THIS DEVLIEG CAT50 FACE MILL HOLDER WITH EXTENSION IS A SPECIALIZED TOOL HOLDER FEATURING A CAT 50 TOOL HOLDER TYPE. THE UNIT HAS AN OVERALL LENGTH (OAL) OF 10.5 INCHES, A PROJECTION OF 6.75 INCHES, A BODY DIAMETER OF 4.86 INCHES, AND A BORE DIAMETER OF 0.5 INCHES.