These are Tech building in the real time strategy game Command & Conquer Generals and its expanison Zero Hour
Tech Oil Derrick
When captured, the tech oil derrick gives a $1000 "finder's fee" to the first person to capture it. It slowly generates funds($200)for the owner.
Owning a Tech Refinery allows vehicles and aircraft to be built at a reduced price.
Holding a Tech Hospital allows all of the player's infantry to self heal.
Tech Repair Pad
Possession of a Tech Repair Bay allows all of the player's vehicles to slowly self-heal to full health. Available in Zero Hour only.
Tech Artillery Platform
The Tech Artillery Platform fires a long range shot against enemies if the player has captured one. It is available in Zero Hour only.
The Tech Reinforcement Pad drops one of the player's faction's main battle tank. For the demolition general, it sends two terrorist combat cycles. This tech building is available in Zero Hour only.
The tunnel works like a GLA tunnel network, able to transport infantry and vehicles. It cannot be captured.It appears in the map for Generals Challenge against the Demolition General. (Removed from game, Only available through mods check big files)