Aerator key is used to assist in the safe removal of standard continental size aerators from tap mixer outlets and prevents from scratches while installing. Water outflow (consumption) limiter. Special overlay, being mounted in tub mixer or shower mixer. Just as tap insert in washstand mixers causes decrease of the liquid flow stream up to 9 litres per minute and simultaneously allows the user to enjoy the unchanged and effective cascade of water diffusion. High performance of the limiter allows to save annually up to 100gbp in water consumption.