Armored Duct

Armored Duct is a transport block that moves items forward along a single direction while explicitly rejecting side inputs from non-duct transport blocks. It functions as a unidirectional duct intended to control flow where adjacent conveyor lines or output faces might otherwise feed into a transport lane. Armored Duct consumes no power or items to operate and simply advances items straight ahead along its facing.

The block's primary role is to prevent unintended transfers into a duct line: producers placed next to an Armored Duct will not have their outputs siphoned into the duct from the side, so the duct acts as a deliberate channel for items rather than a passive sink. This makes Armored Duct useful when laying tidy transport networks around factories and when isolating lanes so only explicitly connected inputs feed them. On some maps and with related blocks, similar side-input rejection behavior is observed (for example, the Armored Conveyor also refuses side inputs from transport blocks on Erekir).

Armored Duct does not grant an armor stat despite its name; it functions purely as a transport element rather than providing defensive properties. It requires no consumption to move items and behaves identically to a forward-moving duct except for its side-input rejection rules.

• Use Armored Duct to prevent adjacent buildings or conveyors from accidentally dumping items into a lane; place it where you need a guaranteed forward-only path.
• Pair Armored Ducts with producers whose outputs you want to route manually rather than let them bleed into neighboring lines.
• Because it refuses non-duct side inputs, use Armored Ducts to separate parallel conveyor lanes that run close together without adding extra routing complexity.
• The block has a Reinforced upgrade entry listed as "Super-speed (both tech branches)" in some sources; this indicates a reinforcement/upgrade path that increases throughput characteristics under the Reinforced designation.