Dongguan Enuo mold Co., Ltd ndi kampani yothandizidwa ndi Hong Kong BHD Group, ndipo bizinesi yake yaikulu ndi kupanga nkhungu zopaka jakisoni ndi kupanga jekeseni. Kuphatikiza apo, nkhungu ya Enuo ndi fakitale ya OEM yomwe imagwira ntchito yowunikira zinthu/Gauge R&D, Die casting, CNC machining, Prototype products R&D, Parts spraying ndi assembling.
Chibolibolichi chimakhala ndi zigawo ziwiri zazikulu, chiboliboli chopangira jekeseni (A plate) ndi chiboliboli chopangira jekeseni (B plate). Zigawozi zimatchedwanso moulder ndi moulder maker. Utomoni wa pulasitiki umalowa mu chiboliboli kudzera mu sprue kapena chipata mu chiboliboli chopangira jekeseni; sprue bushing ndi yomangirira mwamphamvu pa nozzle ya mbiya yopangira jekeseni ya makina opangira jekeseni ndikulola pulasitiki yosungunuka kuyenda kuchokera mu chiboliboli kupita mu chiboliboli, chomwe chimadziwikanso kuti cavity. Sprue bushing imatsogolera pulasitiki yosungunuka kupita ku cavity img kudzera mu njira zomwe zimapangidwa pamaso pa mbale za A ndi B. Njirazi zimalola pulasitiki kuyenda m'mbali mwawo, kotero amatchedwa runners. Pulasitiki yosungunuka imadutsa mu runner ndikulowa mu chipata chimodzi kapena zingapo zapadera ndikulowa mu cavity geometry kuti apange gawo lomwe mukufuna.
Ngakhale kuti kuyerekeza chiwerengero choyambirira cha anthu okhala ku North America panthawi yomwe anthu a ku Ulaya ankakumana ndi anthu n’kovuta, James Mooney anayesa kugwiritsa ntchito zolemba zakale kumayambiriro kwa zaka za m’ma 1900 pogwiritsa ntchito zolemba zakale kuti ayerekezere chiwerengero cha anthu okhala kumpoto kwa Mexico mu 1600. M’zaka zaposachedwapa, Douglas H. Ubelaker wa ku Smithsonian Institution wasintha ziwerengerozi. Ngakhale kuti Ubelaker anayerekezera kuti panali anthu okwana 92,916 m’mayiko akum’mwera kwa Atlantic ndi anthu okwana 473,616 m’mayiko aku Gulf, akatswiri ambiri amaona chiwerengerochi ngati chotsika kwambiri.
