Description Manuals Videos Articles Popular Accessories Clemco #29868 Clemco CMS-4 CO Monitor replacement hydrophobic filter. A new hydrophobic filter is required when changing the CMS-4 Sensor, part #29768. (Sold Individually) Related Parts (1) Parts Included (1) CMS-4 CO Monitor, monitor only #29766 $763.72 1137 Customers Also Viewed CMS-4 Battery Retainer Gasket #29772 $12.81 CMS-4 Battery Retainer #29770 $12.81 Clemco CFP-4C Nylon Coupler with 1-1/4 inch t… #21734 $58.53