Metro 201 Electric, Large Wax Warmer - Petra A power cord is used to obtain energy for a safe heat source to melt Metro 201 Fragrance Cubes NO FLAME; Our wickless warmers will leave no soot residue. Easy cleanup! MELTS FRAGRANCE WAX CUBES to fill your room with a wonderful aroma! SAFE, CLEAN HEAT SOURCE! Illuminated soft light provides a gentle glow to your kitchen, room, or bathroom WAX CUBES SOLD SEPARATELY. Try all of our variety of highly fragranced, custom-scented wax cubes.