Gels are normally placed in Gel Frames (aka Color Frames), which is a metal or flame-retardant paper frame that holds the gel. This ensures the gels do not wrinkle from the heat as much as they would otherwise and also that they do not bend and fall out of the light. Metal frames are used in most applications because they are more sturdy, and last longer. Paper frames are sometimes used in positions where the lighting instrument will be placed above the audience. The frames are put into the color frame slot at the front of the lighting instrument to color the light.