I've noticed some people complaining about his ability to store his knives in robot mode, so when I managed to snag a Ratchet at a Walmart in RI I took a good look at him to see if there's any possibility of a knife storage.
He has these two rectangular nobs on the back of his shoulders. The knives fit perfect, if not a little flimsy because of the material used for the knives.
I like to point mine up and it give a cool winged look.

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