The Disc is a round disc composed of pressed fibres that are impregnated with the active substance Neutrox Gamma. They work in a similar way to the membranes, namely by convection (air movement by means of flow). The Discs can be used in the Easy Twist, the Vaportronic and the Compact. They are available as 6 gram discs or 12 gram discs in the odours neutral and lemon.