… of a kind used for building or construction purposes; glass cubes and other glass smallwares, whether or not on a …
Explanatory notes
… of a kind used for building or construction purposes; glass cubes and other glass smallwares, whether or not on a … hollow bricks, squares, tiles, slabs and various mouldings (double-headed, etc.). The heading also includes … a specific gravity not exceeding 0.5 (hence its use as a substitute for cork), and is easily drilled, sawn, filed, …