Idayamitha engaphezulu yesikulufu se-countersunk inkulu, futhi ingaba yindilinga noma i-hexagonal, ukuze amathuluzi anjenge-screwdriver noma i-wrench akwazi ukujika isikulufu.Ingaphezulu eliphumele ngaphandle liphinde livimbele isikulufu ekubholeni sijule kakhulu ngento futhi sinyuse ukucindezelwa kwesikulufu kokubalulekile.Izikulufu ze-Countersunk ngokuvamile zingasuswa noma zifakwe kabusha ngokuthanda kwazo ngaphandle kokuphazamisa ukusebenza kahle kwazo, futhi zinganikeza amandla amakhulu kunezinzipho, futhi zingaphinda zisetshenziswe.Inhloko yesikulufu se-countersunk ingacwiliswa ngokuphelele ezintweni zomkhiqizo, futhi isikulufu sekhanda ngeke sidlale indima yokuvimbela.
Okuvame ukusetshenziswa ezintweni zikagesi, imishini ye-elekthronikhi, okokusebenza kwemishini, izinto zikagesi zasendlini, imikhiqizo yedijithali, amaphrojekthi okonga amanzi, umhlobiso nokwakhiwa, njll.
