Whether you are installing windows or doors, leveling floors, ceilings, or furniture, building a substructure for a terrace or stairs, or completing other tasks in drywall and interior construction - with these leveling pads, you are perfectly equipped to fill gaps and balance height differences. The set of 144 glazing blocks includes 6 different thicknesses ranging from 1 to 6 mm and is made of PP plastic. Note: Due to temperature fluctuations of the plastic, the glazing blocks may expand or shrink by up to 5%.