The blufixx starter kit includes the blufixx pen, two 7G cartridges(one clear and one black), the blulight LED and a file. Easy to apply: no sticky fingers, no solvents! fill and seal cracks and holes in almost any material. Used for filling in and remodeling flaws in a material. Sealing-up seams and spliced wires. Repairing and binding without use of pressure (e.G. When making models). no prior knowledge is necessary to apply blufixx – simply try it out and repair, design, BF14SK and unleash your creativity, however you please.