Thermochromic Banger with sand inside will heat quartz banger and you will see the sand change color. Torch the quartz bucket and the thermochromic sand heats up to 500 Degrees creating that long lasting dab session. Best banger and the sand turns bright red! 14mm Male 90 Degree Color Changing Thermal Quartz Banger. Quartz Thermal Sand Banger! 4mm Thick Quartz Double Wall Highest Quality. 14mm male Thermochromic Banger with red sand.