Single pen adapter. This adapter is great for applying alcohol inks and making perfect painted lines around your pen while it spins. Adapter comes with 3 clips and paint saber to make spray painting your base coat easier. Adapter goes on your cup turner with no modifications, making creating your custom pens easier. *** If your cup turner pvc/ wooden rod says 1/2 inch on the side you need the 1/2-inch kit. If it does not say anything you measure from side to side and if it measures 13/16ths of an inch (or a little over 3/4 of an inch) you need the 1/2-inch kit. If it measures a little over an inch, then you need the 3/4-inch kit. ******If you can't figure the size out and need help you can contact me on my Facebook page @ imagination 3d and i will be glad to help you. ******* Colors may vary. Not guaranteed a certain color. ****NOT RESPONIBLE FOR WRONG SIZE ORDERS****