Chinese calligraphy brushes are traditionally graded by the hair: weasel hair is stiff and springs back, which suits small precise characters; goat hair is soft and holds more ink, which suits large flowing strokes. Most working brushes blend the two.
These three arrive with the tips stiffened in a natural gum, which is how they are shipped — rinse in cool water and the hairs separate. Never leave a brush standing point-down in water; it will bend the tip permanently.