Native products: mainly to give a gift. It is not recommended to send something that takes up space and is worthless. You can't send it.
Real life: this kind of gift mainly shows concern for the leader.
Seasons and festivals: it is normal to give a moon cake in Mid-Autumn Festival and a new year's goods in Spring Festival.
Give whatever you like: leaders like to drink tea and send tea sets; Leaders like calligraphy, sending sets of books and so on.