A hot glue gun is a hand-held, pistol-like device that heats a round stick of solid adhesive, so that when it melts, and a user pulls the trigger, the melted glue can be squirted out of the nozzle at the gun's tip. Hot glue guns (also called hot-melt glue guns) are used to bond a broad range of materials. Most hardware stores and many department stores carry hot glue guns and glue sticks. Many brands are sold, varying in quality and price. Some accept nozzles having openings producing extrusions of different sizes and shapes. Most are electrical, some use batteries, and some burn butane gas. The sticks can vary in width and length (from 4-12 inches), color, translucence, and viscosity, as well as in the temperature required to melt the glue. Although lower melting point guns and glues are safer to use, the strongest glues are those with higher melting-points, and set rapidly, bonding in 30 to 60 seconds.