Yes. Park multi-tool. Forget which one. I've used it on occassion to make fit adjustments mid-ride: saddle up/down, cleat loosened up, etc. Very handy, I don't ride without it.
'Sides, one never knows when one will have to help someone else out on the road.
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--José
'92 Bianchi Eros
'05 Bianchi Virata
'08 Electra Straight 8 Cruiser