Minor Tank transfer valves can't be seen when held

[Sundance]

So I was rooting around 2016 release to check for a sprite for plasma tanks so I could have something to reference for an in-hand sprite when I noticed something:

In hand_general.dmi there's literally a sprite of it.





I checked it out to make sure that it's a proper sprite and not some broken left over thing of the past but nope:


Overlaying it seems it works just fine. So there's no real point in me spriting it.. it's already done.

This seems like a very simple fix, the icon states or something (i dunno, not a coder) are missing this for some reason.