 So is the idea of the bandage that it would emit the light in exactly the right place so that you then got whatever treatment there is that would make a difference to the wound? Exactly. So one of the things that we're looking at is whether we can create really compact deep UV light sources combined with special optical fibres to then kind of diffusively deliver that deep UV light to the wound. But that's not easy, right? So making these wavelengths...