MNG Duravent 46DVA-DC Direct VentPro 4"X"6 Round Support Cover. The 46DVA-DC is a genuine product manufactured by Duravent and has an Aluminum Construction. This particular product is a Round Support Cover, which is part of MNG Duravent's DirectVent Pro Collection. This wall cover can be used as a decorative cover with its sharp black finish. It is for use with "flat ceiling installations" and "horizontal" (through-wall) installations. The DirectVent Pro collection of ductwork is a unitized, coaxial venting system and it is designed for use with fireplaces, propane stoves,and direct vent gas or propane stoves.