As of 1.106, this is one of the only three crafting components required to make a Nuclear Reactor and will extend reactor's inventory by 1 column. The chambers also no longer help to cool the reactor, and they protect the reactor from any outside influences to its temperature, i.e., water and lava.
| Industrial Craft²
|| Reactor Chambers were re-released as part of the 1st Nuclear Revolution. They had a different recipe. |
|| Reactor Chambers had their recipe changed again, as part of the 2nd Nuclear Revolution.