This 5 pack of Yocan Evolve Plus XL Coil Caps is meant for use with the Yocan Evolve Plus XL atomizers. These caps screw onto the Yocan Evolve Plus XL atomizers to prevent wax from leaking and promote better heating. The coil caps lock in hot air as the four quartz heating elements of the atomizers (sold separately) generate huge dab-like rips.