The T-Cycle RANS V2/Formula Idler Kit is a beautifully machined compliment to your RANS V2 or Formula. Super durable mounting plates hold each a Power and a Return idler. This kit is sure to give you a boost of performance power in your rear wheel, as well as substantially quiet the chainline. RANS installed two different frame mounting bosses on their bikes. The width is either 1-1/4" or 1-5/8". Remember this is the left to right width of the actual mounting boss, not the front to back distance between the two mounting bosses.