A tolerance strip is formed a strip of resilient material with corrugations, the corrugations extending transversely across the full width of the strip, the corrugations defining crests with troughs between adjacent corrugations, a central portion of the corrugations being of substantially uniform height across the strip, portions of the corrugations adjacent each longitudinal edge of the strip decreasing in height towards the edge of the strip. In one form the corrugations are flat longitudinally of the strip at the crests and/or troughs.