Authentic products: strip-shaped, consisting of a worm body and a fungus base, with a total length of about 9- 12 cm. The worm body is like a dried silkworm, about 3-6 cm, and about 0.4-0.7 cm thick. It is dark yellow and medium yellow-brown, with rough appearance and obvious ring patterns, with 20-30 links and 8 pairs of abdomen, located in the middle of the worm body. The fungus seat grows from the insect head, curved and rod-shaped, with a slightly larger upper part, grayish brown or dark brown, empty cross-section and pink white. It tastes slightly bitter and slightly fishy.

Fake products: Most of them are dried roots of the Labiatae plant Stachys sieboldii (also known as Bombyx Batryticatus), with a spindle-like shape, yellowish to grayish yellow surface, obviously fewer links than the real product, only 2- 1 1 piece, no abdomen, larva-like, no daughter seat, crisp texture, easy to break, white and powdery cross section, and no straw mushroom in the mouth. In addition, there are fake Cordyceps made of starch, flour, corn flour, a little gum and pigment, and some inferior Cordyceps with metal wires inserted in the insect body, which are not suitable for purchase.