Used for 90W or big Machine, 3 pin connection pls check with your current machine. if you have a 4 pin, you need to change the motor Instructions of the Rotary Attachment Disconnect the Y-motor from the Y-driver. Plug in the rotary attachments plug, into the Y-driver. Put the rotary attachment on the work table. Attach the object to the rotary attachment. Modify the moving distance parameter of the Y-axis. The distance can be indicated to be πD/2. (D = the diameter of object) Adjust the focus. Start the engraving. Maximum length of Stock: 25” Chuck Size: 3” Chuck Bore Size: 0.5” Width: 6.5 ”Total Length: 35” Height: 7.5”