These are sold separately!
These are a simple way to adjust bike chain line. Precision alloy washers made to specific thickness; by adding one or more to each bolt between the crank and the chainwheel you can move it outboard (or inboard, in instances where the chainwheel is inboard of the spider) by a finite amount. Obviously you need to make sure your chainwheel bolts are long enough to accommodate the extra thickness and you may want to substitute a longer set if you make large adjustments. Not elegant by any means, but effective. One of my single speed MTB's run these which is a good application because it runs an external cup bottom bracket which has less scope for lateral adjustment than was the case with square taper BB's.
Various brands, Wheels Mfg predominates
|Brand||One-Off's and unbranded|