This new Grace Glass with a straight tube from the Mill Series is a strurdy piece of borosilicate. Created with a designe inspired from the Dutch Mill art percolator and this bong has 18.8mm parts. The thickness of the base is 15 mm. Equipped with a new Mill percolator it will come also with ice notches to hold some ice cubes and cool the smoke. You need to have this piece into your collection!