when installing the asr brace, how long does the lca bolt need to be?

i've got everything ready and about to install but looking at the lca bolt that i have in front of me (it's only 12cm long). the bolt needs to go through the asr brace, the lca, and pop out the otherside. is 12cm enough?

is the oem bolt long enough?

btw, it's for a stock em1