The Cap is a special structure which snaps onto a pipe entrance. When placed onto a pipe entrance, it will stop any iridium from flowing out of it. If the pipe entrance was previously leaking, the Cap will prevent the loss of iridium from the leak.

Another more expensive, but more adaptive way of blocking pipes is the Valve.


The Cap is a very useful structure for anticipating a pipe network's expansion. Caps have the special property of being vulnerable to the Portafab, being destroyed by it in 2 hits or less. If a T-Junction or a Four-Way is placed down but not all of its entrances are needed at the present time, the Cap is a very effective means of ensuring no iridium is lost unnecessarily to leaks.

Pipes PipeT-JunctionFour-WayElbow
Extractors Well PumpCondenserSubmersibleCrystal Resonator
Tanks Small TankStandard TankLarge TankReservoir
Special CapDistributor CapRefill StationValveDrop Tank
Defense WallKeepGate
Basic Ladder BlockLight SourceLight Post
Blocks BlockHollowBlockPlatform BlockSlab Block
Wedges Wedge 30Wedge 45
Shield GeneratorPriority Beacon
Production ArsenalGarageS.S.I.M
Weapons/Defensive TurretArc TurretPoint Defense
Weapons/Offensive BoreArtillery
Spawn PointUpgrade Station
Structure Technology FabricatorAutomechanic
Miscellaneous Technology Boost PadDistributorSpatial AnchorTransceiver