Posterior division of retromandibular vein
Ramus posterior venae retromandibularis · Zadní větev zadočelistní žíly
Veins
Looks like
The back branch of the retromandibular vein, leaving the lower parotid gland behind the angle of the jaw.
What it does
Joins the posterior auricular vein to form the external jugular vein.
Keeping it well
Mostly a surgical landmark near the parotid gland and the facial nerve.