Abstract: Reactors (medical devices), which contains one or more independent of each other solutions and has two or more openings with corresponding indented hollow caps and/or pump and/or needle on the other opening as delivery system. The caps contain within them sensitive or incompatible enzymes, chemical, biological, or synthetic substances in powder or tablet form. Indicative of these caps is the fact that when impressed or twisted the protective seal within is broken, releasing their content into the solution or solutions contained within the vial in the order where the desired reactions will take place and the final products will be used by the user for pharmaceutical, cosmetic, nutritional, diagnostic, and other purposes.