Ceramic head (mixer head) - so called mixer’s hart - it factor of stability and leaproofness. Ceramic heads ensure precise regulation of the quantity of flowing water and they are responsible for proportional mixing of warm and cold water.
Cluster (according to Vikipedia, one of the meanings) - spatially concentrated group of companies, institutions and organization linked by the network of vertical and horizontal relationships, often of informal nature, which by focusing the specific resources enables those businesses to achieve sustainable competitive predominance.
Tap insert - filter which is being mounted on the end of the washstand or drainboard sink mixer outflow; fine mesh or special arrangement of openings through which water flows. It optically enhances the water stream by the significant aeration of water and thanks to that, it limits the water consumption from 15 up to even 60%.