The Cabinet Ventilation grille is a 4.6 by 4.6 inch metal grille that can be installed into cabinets and walls to help increase ventilation. It can also be used in conjunction with a fan system to act as a passive intake or exhaust vent. The kit includes an optional 80mm fan guard and hardware to secure a 80mm fan, the most popular size for computers and DIY applications, onto the grille. To mount your fan and grille into your cabinet or wall, you would need to cut a square hole approximately 3.42 by 3.42 inches. Features a CNC machined aluminum frame with a brushed black finish; pre-secured to a steel honeycomb grille with four screws. Information on the additional included hardware can be found below.