A unique treatment for pigments is provided. The methods may include the steps of providing a nanoscale fiber film material comprising a plurality of nanoscale fibers ; and irradiating the nanoscale fiber film material with a controlled amount of radiation in the open air or in a controlled atmosphere. The braking assembly characterised in that the actuating means comprises opposed first and second actuating levers arranged to provide a balanced force to each of the braking members such that even braking of both wheel mounting assemblies is affected when the trigger assembly is engaged.