About this 3D model
This monkey is wearing a bottle cap as a hat. Meshmixer and Blender were used to hollow the monkey and then union a PCF-33P thread to the top. These caps are about 33mm across and are found on 8oz juice or non-carbonated drink bottles like these (check your grocery store): https://www.amazon.com/Motts-Apple-Juice-Pack/dp/B01IRHDZKY