Tempering or toughening the glass through heat-treatment makes it stronger and safer for commercial and residential use. tempered glass is four to five times stronger than annealed, or untreated, glass and has increased tensile strength, thermal shock resistance, heat withstanding capacity, and safety. Calisto Glass Undertakes glass tempering jobs from 4MM to 19MM in thickness. We are the first in Qatar to install Kera Glass Tempering Plant from Italy, which is considered the best of its kind in the world. It meets the productivity and quality standards of medium to large companies in the market.