I got "Banpeiyu" from my parents on the end of last year. It is a special product of Kumamoto Prefecture ( Yatsushiro area) and a citrus fruit of the world's largest class.
The place of origin is Malay Peninsula, and it was introduced into Japan in 1920. The weight is about two kilograms, and they have a unique fresh smell, thick skin, plain taste and not much fruit juice.
I made sweet in the part of the skin. The fruit and skin were both delicious!