Sistimi ea siling ea grid e arotsoe ka likhopo tse kholo tsa grille, likhopo tse thusang le sistimi e kaholimo ea keel. Ho tšoana ha likhopo tse ka sehloohong le likhopo tse thusang tsa grille li bua ka li-slats tse sekoti tsa tšepe. Siling ea siling ke siling e bulehileng ea mokhabiso e entsoeng ka motsoako oa likhopo tse kholo le likhopo tse thusang tsa grille ka mokhoa o otlolohileng le o tšekaletseng.