Sith trooper armor is the distinctive red, high-performance armor worn by the Sith Eternal's army in Star Wars: The Rise of Skywalker. Based on First Order stormtrooper design but constructed from superior, quadruple-layered gammaplast, it features a crimson color designed to evoke blood and lightsabers, often including specialized technology like sensors and filtration systems. 

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Key details about Sith trooper armor include:

• Design & Color: Similar in shape to First Order stormtrooper armor, the armor is distinctively bright red.
• Material: The armor is constructed from gammaplast, which provides superior durability over the betaplast used in standard First Order armor.
• Technological Upgrades: It features a shoulder-mounted sensor telemetry pod, a data antenna, a filtration system, and a, data storage module.
• Structure: It is designed with "faceted angles" to help redirect blaster bolts and utilizes anisotropic bands to increase surface area for improved damage reduction.
• Appearance: The armor is worn over a black, corrugated body glove, creating a menacing, fully encased, "faceless" appearance.