Leli block lokuba kwi-combi lufakile ngokubanzi ukuthi lwedluleyo, lwefillayo, kunye nolwesihlawulo. Ngenxa yokusebenziswa okujwayelekile kweelektri, imikhaniki kunye neemfuyo, kunye nokudibana ngaphandle kwisistemu seservo. I-combi siyaziqondisi zonke izinhlobo ezimbili kunye nokuzalwa kokuqala komoya.
I-block leCombi yezilungiselelo zePET lihluhlwe ngokushesha kumakhi oshesha lokuhlula amafomu, makhi oshesha lokulula amafomu kunye nomakhi oshesha lokusihlawula, lifakile nesistemu lokuhlola kunye nenqanawe yenqanawe.