Sab saum toj txoj kab uas hla ntawm countersunk ntsia hlau yog loj, thiab nws yuav ua tau puag ncig los yog hexagonal, yog li ntawd cov cuab yeej xws li ntswj ntsia hlau los yog ciaj ntswj tuaj yeem tig cov ntsia hlau.Sab saum toj protruding tseem tiv thaiv cov ntsia hlau los ntawm qhov tob tob los ntawm cov khoom siv thiab ua kom lub siab ntawm cov ntsia hlau rau ntawm cov khoom.Countersunk screws feem ntau tuaj yeem raug tshem tawm lossis rov muab tso rau ntawm qhov xav tau yam tsis muaj kev cuam tshuam rau lawv cov kev ua tau zoo, thiab tuaj yeem muab lub zog ntau dua li cov rau tes, thiab tuaj yeem rov qab siv dua.Lub taub hau ntawm countersunk ntsia hlau tuaj yeem ua rau tag nrho ntawm cov khoom siv, thiab lub taub hau ntsia hlau yuav tsis ua lub luag haujlwm thaiv.
Feem ntau siv hauv cov khoom siv hluav taws xob, tshuab hluav taws xob, khoom siv tshuab, khoom siv hauv tsev, cov khoom siv digital, cov dej txuag dej, kho kom zoo nkauj thiab kev tsim kho, thiab lwm yam
