Check the listing for details. Command BT40 Shell Face Mill Tool Holder Stud 3/4" 1" or 1-1/4" Arbor Size Cat40. Condition: Used. Listed at 66.99 USD. These are being sold as singles, if you buy more than one, the rest will have FREE shipping. They are all in pretty much perfect condition. They have the 16mm thread Pull Studs /Screws. These are compatible as Cat40 tool holders and Cat 40 machines, you just need to change-up your Pull-Stud configuration, or they need to manually be installed in the machine. The Large Allen head mill mounting bolts only come with the first ones sold.(as soon as they are gone, they are gone)Here is what is all here to choose from:(A,B, and C) The left ones are the 3/4" diameter arbor(mill center hole size) w/ 5/16" wide drive lugs and 3/8" NF bolt hole(D,E and F) The Center ones are the 1.0" diameter arbor(Mill center arbor hole size) w/ 3/8" wide drive lugs and 1/2" NF bolt hole( G) is the Right One , it has 1-1/4" diameter arbor(Mill center arbor hole size) and 5/8" nf bolt hole sizePlease let us know right away what tool holder(s) you are choosing, We have to ship within 24 hoursIt is to your benefit to buy more than one, because of the free shipping after your first one deal. We have many other tool holders for sale, look at our ebay-store and use some of these key words: BT40 Holder collet Tool CAT40 CAT50 BT35 NMTB50 Guhring Kaiser CV50 HSK Skully Jones ...We have all types of tooling for sale..Look over Our Ebay Store and combine items for only 9.99 shipping cost for all.