Abstract: A lagging material for application to the surface of a pulley, said material being integrally formed in elongate strip form and having an upper surface including a plurality of discrete nodules extending therefrom and arranged regularly or randomly according to a predetermined pattern and including a plurality of longitudinally spaced apart elongate and transversely extending cutting sipes laterally defined by the nodules so as to form a partial or complete boundary wall of each sipe; wherein said nodules are arranged over the upper surface of said material so as to allow cutting of a predetermined size of lagging from a larger sheet or strip of said lagging by effecting cuts along or across said cutting sipes and between said nodules.