Stackable washer.

摘要

A stackable roofing washer (18) which has a central aperture (20) which can receive a fastener which passes through a roofing material and into the roofing underlay. The washer (18) has at least one notch (64, 66) in its periphery which can co-operate with a rib in a chute of a washer dispensing machine to prevent a stack of the washers from cascading when the chute is tipped.