Manhole grate muaj cov qauv yooj yim, feem ntau muaj cov thav duab thiab sawb -zoo li tus lossis mesh- zoo li cov ntxaij lim dej, thiab feem ntau yog ua los ntawm cov hlau cam, stainless hlau, lossis cov khoom sib xyaw (xws li fiberglass). Lawv cov qauv tsim qhia txog kev ua haujlwm ntawm cov kua dej thiab kev tiv thaiv corrosion; Piv txwv li, cam khwb cia hlau manhole grate undergo xeb- pov thawj kev kho mob kom ntev lawv lub neej kev pab.
Manhole npog, ntawm qhov tod tes, muaj cov qauv siv ntau dua, feem ntau muaj cov npog lub cev thiab lub hauv paus. Lub hau npog tuaj yeem yog cov khoom siv los yog ntim nrog cov pob zeb kom txhim kho nws cov load-cov kabmob muaj peev xwm; lub hauv paus yog siv los tuav lub hau npog lub cev thiab tiv thaiv kev txav mus los. Hais txog cov ntaub ntawv, manhole npog muaj ntau yam kev xaiv, suav nrog cov hlau cam khwb cia, cov hlau nplaum, cov ntaub ntawv sib xyaw (xws li BMC), thiab pob zeb. Ntawm cov no, ductile hlau manhole npog yog dav siv nyob rau hauv cov tsheb khiav tsheb vim lawv lub zog siab thiab toughness.
