I know it's not OCP, but the handlebar bag is my favorite place for my wallet, phone, keys, etc. It pops right off, has a shoulder strap, and is in full view and accessible while riding. I like having my 'stuff' with me, because when I ride there is no telling where I might decide to stop...especially if the GF is with me and we come upon a flea market, craft show, garage sale, or just about any shop that looks interesting...to her!
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"Let us hope our weapons are never needed --but do not forget what the common people knew when they demanded the Bill of Rights: An armed citizenry is the first defense, the best defense, and the final defense against tyranny. If guns are outlawed, only the government will have guns. Only the police, the secret police, the military, the hired servants of our rulers. Only the government -- and a few outlaws. I intend to be among the outlaws" - Edward Abbey