Plastic internal grille and louvre vents designed to cover the inner opening of a cavity sleeve and provide an aesthetically pleasing appearance while sustaining airflow and reducing drafts. All grilles, including the hitPlastic internal grille and louvre vents designed to cover the inner opening of a cavity sleeve and provide an aesthetically pleasing appearance while sustaining airflow and reducing drafts. All grilles, including the hit and miss, feature the same louvred design....View more