Warnings at the top so you read them:
This design is provided as-is, with no warranties expressed or implied. Use at your own risk.
Anyway, about the design:
A while back, it was hard to find Tylenol. Often we could get children's tylenol but not infant's tylenol. They came in the same concentration, the only difference was the packaging. And the packaging of children's tylenol was difficult to use with our toddler - we had to use the syringe, and you can't put the syringe directly into the top of the children's tylenol bottle like you can with the infant's tylenol. This adapter fixes that: you can screw this onto a children's tylenol bottle, and put the syringe from infant's tylenol into the top of this adapter to fill it up.
Two sizes are provided:
Prints without supports if you put it with the “female” thread end upward and the syringe hole downward.
The author marked this model as their own original creation.