The Curve sole measurement tool works in conjunction with their flat sole shims to correct the radius of flat sole shoes and prevent unwanted squeaking. There are 4 radius measurements, one per side, that measure the sole and indicate whether a shim is needed or not.

• The Curve sole measurement tool works in conjunction with their flat sole shims to correct the radius of flat sole shoes and prevent unwanted squeaking. There are 4 radius measurements, one per side, that measure the sole and indicate whether a shim is needed or not.