Icons in right click menu of fuel tanks

[jebodiah1976]

What are these icons that appear when you right click on a fuel tank, or a battery (or pretty much anything with a resource). It's like a play button and a disabled sign.

I have clicked on oxidizer here so you'd see what I mean.

Edited August 17, 2014 by jebodiah1976

[Tex_NL]

Those are to toggle fuel flow from that tank. When the disabled sign is showing no engine will pull that resource from that tank. You can however manually draw fuel from it to any other tank.

[Pecan]

As explained by Tex. With a battery it is useful to disable the flow on a unmanned probe-cores so they do not drain and can be used as an 'emergency reserve' should you ever find yourself out of power and needing to deploy solar panels, orientate the ship, etc.