It is called Japanese Sencha because not all Sencha on the market is from Japan.
This Sencha is a very fine one from the central Shizuoka province, and can be found in many homes in Tokyo. It is supplied by the Kaburagi family that has sold to Americans for over 110 years. They are well known in Tokyo and throughout Japan as a pre-eminent supplier of tea.
As a mid-season Sencha, it has good levels of amino acids and more body than most green teas. It is a very pleasant green tea, a fine choice for everyday.