They just clamped them in a Collet Chuck with a 1 collet. These use DA100 Collets with a range of 1/32" - 9/16" or 1mm - 14mm. Metro Rack Thanks for Looking! There is a 14 day return privilege if the item arrives not as described or non-functional unless otherwise stated in the description.This is not a satisfaction guarantee, I will only honor a return if we miss-listed the items or it does not function properly. If you have any questions please let us know. Auctiva offers Free Image Hosting and Editing. This item is in the category "Business & Industrial\CNC, Metalworking & Manufacturing\Workholding & Toolholding\Workholding\Chucks\Collet Chucks". The seller is "framframllc" and is located in this country: US. This item can be shipped worldwide.