They are 8mm. They are listed to fit the following Honda models; TRX250, TRX400FW, TRX450ES, TRX250TE, TRX400FGA, TRX450FE, TRX250TM, TRX420TE, TRX500, TRX350FE, TRX420TM, TRX650, TRX350FM, TRX450FA, TRX680, TRX350TE, TRX450S, TRX700XX. AND MANY OTHERS.
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