Serpent guard

From The Stargate Omnipedia

Serpentguard2.jpg

A serpent-helmeted Jaffa in loyal service to Apophis's forces and family. The guard bears armor made in the likeness of a serpent, in keeping with Apophis's symbol and mythological persona. The serpent helmet is retractable, opening at the center to reveal the wear's head within.

Serpent guard are usually assigned to guard facilities and occasionally to accompany their master on limited excursions. When entering the field of combat Apophis's Jaffa are more likely to fight without the helmet. Indeed, it is possible that the helmet is reserved only for an elite few chosen for the Goa'uld's personal guard.

KEY EPISODES

Children of the Gods - Serpent guards precede Apophis through Earth's Stargate as he searches for a new host for Amonet.
Out of Mind - Serpent and Horus guards pair up in defense of Hathor's fortress.