Plastic Bottle Cap Opener

My son-in-law has arthritis and has been having trouble opening water bottles. The original design looked intriguing, but since it was designed to open soda bottles it was too large to open water bottles. Water bottles typically have diameters from 25 to 27 mm, while soda bottles are typically around 30 mm. I wanted something that could be used for either water or soda bottles. Using the concept from the original design, this remix has a tapered interior (and exterior) shape going from 25 mm at the top to 32 mm at the bottom. I have tested it with soda and water bottles and it seems to work well. I have provided the design with and without the handle. While I have not printed the design without the handle; it is essentially the same as the design with the handle. The design is intended to be printed upside down (with the narrow end on the build plate), as oriented in the STL files. The fin width is 0.8 mm and prints well with a 0.4 mm nozzle.