The Siemens LZ53450 Recirculation Set makes your range hood recirculatory. This means that all cooking fumes from your cookware aren't directed outside, but are instead filtered and blown back into the kitchen. This way, you won't need an air drain in your kitchen. This set consists of all the installation material you need and a filter to convert your range hood. The Siemens LZ53450 is suitable for the Siemens LC97BA532, LC98BE542, LC98BH542, and LF98BE542.