Heat strengthened glass is similar to tempered glass except that the cooling is done at a much slower place.

THICKNESS RANGE SPECIFI- CATION 3-25mm
Min Size:300300mm, MaxSize:33005200mm

CHARACTER OF HEAT STRENGTHENED GLASS
Not easily self-explosion.
It has flatter surface than tempered glass.
Heat strengthened glass is about twice as strong as annealed glass of the same size and thickness.
When broken,the glass fragments are more similar in size and shape to annealed glass fragments and thus tend to stay in the opening longer than fully tempered glass particles