4 easy steps Speedset's rigid vinyl track mechanically locks glass blocks in place horizontally and vertically (see front cover). It fits all brands sold in the other than U.S. Pittsburgh Corning blocks, which have different sidewall profiles and are smaller. See separate outline. A Anchor B Horizontal Track C Vertical Track D Glass Block Silicone 7-1/2" vertical tracks are placed adjoining blocks, between which must be placed straight and plumb.
