Handle Bar Mounting bolt size.

[Bobthecod]

Hi all, I am currently working away from home and away from my bike. I want to order a Iphone holder that uses an inch ball that is bolted on to the handle bar mount. You get an elongated bolt with the set but you have to order the correct size bolt. The options i have are M6, M8, and M10 Bolts. As i dont have my bike with me i cannot get the size, is any one able to assist me in my quest? so i can order and then have it at home waiting for me when i return.

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