Ibyapa bya karubone ya NM400 bizwiho guhangana no guhangana no kuramba, bigatuma bahitamo cyane mubisaba gusaba. Biranzwe no gukomera ku izina rya 400 HBW (Brinell Hardness), aya masahani yagenewe guhangana n’ingirakamaro nyinshi y-imikoreshereze, kwemeza igihe kirekire no kwizerwa mubikorwa bitandukanye byinganda. Kimwe mubyiza byingenzi bya NM400 ni bidasanzwe yabo