Invisible Grille HDB: In Singapore, invisible grilles are used a lot in HDBs, condos, and even offices. They keep people safe by covering the windows and balconies. This is very important for families with young children or pets. Traditional grilles can be big and in the way. Invisible grilles, on the other hand, are hard to see from a distance, don't block the wind or the view, can blend into any background, and don't change the way the inside looks. The price of invisible grilles can change based on things like the size of the window, the type of material used, and the brand.