This is a direct replica of the VESA mount included with the official Cintiq 16 Adjustable stand. This is required to mount the Cintiq 16 to a adjustable arm or other type of mount. Let's be honest, this piece should be included with the Cintiq itself, but now you can print your own!
I recommend gluing a piece of very thin felt, cardboard or something else soft to the narrower side to prevent scratching your Cintiq. I used cereal box cardboard on mine and it works a treat.
Remember, the narrow side attaches to the cintiq, and the wider side attaches to the VESA mount of your choice.
The author hasn't provided the model origin yet.