A ventilated tray, has openings in the bottom of the tray, allowing some air circulation around the cables, water drainage, and allowing some dust to fall through the tray. Small cables may exit the tray through the ventilation openings, which may be either slots or holes punched in the bottom.
Cable trays may have solid covers to protect cables from falling objects, dust, and water. Lighter cable trays like the CABLE-MGR CM10, are more appropriate in situations where a great number of small cables are used, such as for telephone or computer network cables. These trays may are made of wire mesh, called “WIRE BASKET TRAY”, and are designed with side rails to support the cable on either side.