Standard architectural float glass is traded in thicknesses from approximately 2 mm to 19 mm, with thinner gauges used in electronics and display applications and thicker gauges in structural and blast-resistant glazing. Thickness tolerance and flatness specifications vary by end-use and are typically stated in purchase contracts referencing ASTM or EN standards.

Both fall within this heading, but surface ground or polished glass has undergone additional mechanical finishing to achieve superior flatness and parallelism. This distinction matters for end-users in mirror manufacturing and precision optics, where residual surface waviness from the float process would be unacceptable, and it may affect the applicable duty rate at the tariff-line level.