Jaffa helmet

While in the service of the Goa'uld System Lords, the Jaffa guards often wore helmets or masks that hid their features and intimidate the System Lords human slaves. The helmets could be retracted into the body armor of the Jaffa, or take off the armor completely. In addition, the System Lords themselves would often wear masks to deceive their human slaves, or on the (rare) occasion where they would personally join their Jaffa in battle