Vertical profile connector with guide slots for locking in convection grille profiles to create a compact grille unit. The vertical convection grilles can be led down a certain distance on the front of the duct, leaving a gap to the floor for cleaning purposes, or can be led all the way to the floor and secured there with the BVL floor holder. This design is a variant of the convector cover. As an alternative to the convection grille profiles, the heating convectors can also be covered with closed sheet steel panels.