In the case of plants imported from Asian countries, the entire culture system is different - the plants are grown and delivered in "nursery soft pots", with sphagnum.
A 2.5 inch pot, for example, has the actual size of 2.5 inches - but the plant has a similar age and size to a plant grown in Europe with bark, in a 9 cm pot. A 1.7 inch pot is 1.7 inches in actual size - and the plant is similar to a 6 cm potted specimen.
For this reason, on the product page the displayed size will be, for example, the shape (pot 2.5 inch ~ 9cm).
This system is considered effective both for the growth of the car and for the transport of the plants, because everything is reduced to what is strictly necessary for the growth of the plant.