PwnCNC has extra collet nuts available. Our spindle motors will use either ER11A or ER20A nuts. 65mm Frames use ER11A, our 80mm spindles use one or the other ER20A or ER11A. These are not compatible with the ATC System, for that check out ISO20 Tool Holders.
If you're looking for collets... checkout our ER Collets and ER High Precision collet sets options.
Our black collet nuts are all balanced at a standard 14,000 RPMs. This is perfect for woodworking, acrylic, and other low-precision projects.
If you're getting into metalworking... then you'll love our silver collet nuts which are balanced at a whopping 18,000 RPMs. These are the same collet nuts included in our High Precision collet sets.
Learn more about how ER collets work by checking out our KB article on the subject