Cov ntsuas tsis raws cai yog qhov tseem ceeb rau cov khoom siv txhua hnub: xws li cov koob yees duab, tsom iav, watches, electronics, thiab lwm yam. TVs, khoom siv hluav taws xob, seev suab paj nruas, rooj tog thiab lwm yam kev sib tsoo; xws li kev ua vaj tse, kev tsim kho, kev txuas choj siv cov ntsia hlau loj loj, Ntauv; cov khoom siv thauj khoom, aircraft, trams, tsheb, thiab lwm yam yog siv nrog cov ntsia hlau. Screws muaj ib qho tseem ceeb hauv kev lag luam. Tsuav yog muaj kev lag luam hauv lub ntiaj teb, kev ua haujlwm ntawm screws tseem ceeb heev.
Hom ntawm cov ntsia hlau, seb nws yog ib lub viav vias rau cov tsom iav los yog cov ntsia hlau loj rau ib qhov loj-loj hnyav hluav taws xob engineering, muaj ntau hom. Qhov tseeb ntawm qhov ntsuas yog feem ntau ntawm 6g (Qib 2, Asmeskas "IFI" yog 2A), thiab cov ntaub npog siv cov txheej txheem siv yog 1g (Qib 3, "IFI" yog 1A hniav)