@anja
Typical Maine Coon:
Height: 10”-16" | 25-40 cm
Length: 19”-32” | 48-81 cm
Weight: 10-25 lb | 4.5-11.3 kg

Since Amazon boxes are almost always in that range, even for a single pen, Maine Coon is the way to go for your next kitty.

https://www.dimensions.com/element/maine-coon-cat