S&amp;P BOC100 Metal Adjustable Round Grilles<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Exhaust grilles for bathrooms， toilets and other small rooms. All models offer an adjustable central valve to regulate the airflow</li><li>Accessory to S&amp;P Inline Exhaust Fans (PV， TD， SWF)</li><li>4"/100MM metal circular adjustable interior air valve</li></ul></div><img src="http://ecx.images-amazon.com/images/I/31cVQ6f6gZL.jpg" noproxy>