![Aluminum Spindle Spacer Set](http://booneti.com/cdn/shop/products/spindlespacers_{width}x.jpg?v=1671051504)
The spacers are designed to fit over the 30mm spindle to allow fine tuning of the right crankarm to dial in the chainline you want. The set of 4 includes 0.5mm, 1mm, 2mm, and 3mm. This allows spacing from 0.5 to 6.5mm in 0.5mm increments.
30.2mm ID and 34mm OD.