Sistimi e koetsoeng ea Suction ke sistimi e tsoetseng pele e koetsoeng.
E entsoe ka letsoho le sireletsang ho arola likokoana-hloko tse ka hare le ho thusa bahlokomeli ho qoba tšoaetso.
Moralo oa nako e le 'ngoe oa phefumoloho o tla lumella bakuli boiketlo ba ho monya ntle le ho emisa moea oa moea.