The Jacobs CAT V 50 end mill tool holder is designed to hold up to a 1/4-Inch shank cutting tool. It has 4-Inch projection and is prebalanced to 15,000 RPM. The Jacobs CAT V 50 end mill tool holder is used for heavy duty cutting and general milling. The Jacobs CAT V 50 end mill tool holder is able to provide more accurate, rigid tool holder-to-spindle mount tapers. The taper is grounded to AT3. Easy changes and set-ups makes the Jacobs CAT V 50 end mill tool holder a low maintenance product. The Through spindle coolant is standard for all Jacobs end mill tool holders and the Jacobs CAT V 50 end mill tool holder comes with a one year factory warranty