Whether you are installing windows or doors, leveling floors, ceilings, or furniture, building a substructure for a terrace or staircase, or handling other tasks in drywall and interior construction, these leveling pads equip you perfectly to fill gaps and compensate for 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%.