This is an air assist and adjustment knob for the new Ortur Laser adjuster head, the 3D print slide over the lens knob and gets bolted with a 3mm screw against the head. This is perfect for pushing air flow directly down onto your engraved area, it is recommended to print this with full supports except the tube part, the top support is left inside the print which will allow to air to be compressed more and pushed out stronger, the bottom support can then easily be removed