# How to line break a siunitx unit

I made a new command for this unit:

\SI{#1(#3)e#2}{\KBE\per\gram\of{FM}}

But it is so bulky and it seems that latex can t handle the "normal" linebreak. So, my new UNIT is sometimes over the normal text width on the right margin

Is there an siunitx option to handle this, or any other solution?

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Welcome to TeX.sx! While the problem is clear enough, at least to me, it's always a good idea to give a minimal working example (MWE) that illustrates your problem. For example, here other people might not work out what is going on with your units. –  Joseph Wright Sep 5 '12 at 20:43