A torch that uses fuel to heat materials is known as a gas torch or blow torch. The most popular fuels for gas torches are propane and Map Pro (a kind of propane). The most frequent task for which gas torches are employed is soldering copper pipes. Gas torches can also be used to weld some materials, braze metal, strip non-leaded paint, activate shrink wrap and shrink tubing, unstick stuck and rusty bolts, remove air bubbles from epoxy finishes, eliminate weeds, and weld certain materials.