Filter Filters GMC Remove All Filters Price $100-$500 (148) $500 and above (9) Condition New (157) Brand Harmony Audio (157) Model Sierra (140) Sonoma (8) Envoy (7) Canyon (2) 01-06 GMC Sierra 1500 Crew Truck Harmony R104 Ported 10" Sub Box Enclosure $115.99 Compatible with 01-06 GMC Sierra Non-HD Crew Cab Truck Harmony F104 Dual 10"... $405.99 Compatible with 2007-2013 GMC Sierra Extended Cab Truck Harmony R124 Dual 12"... $357.99 Compatible with 2007-2013 GMC Sierra Extended Cab Truck Harmony A122 Single... $315.99 Compatible with 1988-1998 GMC Sierra Ext Cab Truck Harmony F104 Dual 10" Sub... $474.99 Compatible with 2002-2009 GMC Envoy SUV Harmony A122 Single 12" Custom Sub... $391.99 Compatible with 2001-2006 GMC Sierra HD Crew Truck Harmony R104 Dual 10" Sub... $310.99 Compatible with 1988-1998 GMC Sierra Extended Cab Truck Harmony F124 Dual 12"... $460.99 2007-2013 GMC Sierra Crew Cab Truck Harmony A122 Dual 12" Sub Box Enclosure New $290.99 Compatible with 2001-2006 GMC Sierra HD Crew Truck Harmony F104 Dual 10" Sub... $494.99 Compatible with 01-06 GMC Sierra Non-HD Crew Cab Truck Harmony F124 Dual 12"... $435.99 Compatible with 1988-1998 GMC Sierra Extended Cab Truck Harmony R104 Dual 10"... $303.99 Compatible with 1982-2004 GMC Sonoma Extended Cab Truck Harmony F124 Dual 12"... $511.99 2001-2006 GMC Sierra HD Crew Truck Harmony R124 Dual 12" Sub Box Enclosure New $231.99 Compatible with 1982-2004 GMC Sonoma Extended Cab Truck Harmony F124 Dual 12"... $425.99 1982-2004 GMC Sonoma Extended Cab Truck Harmony R124 Dual 12" Sub Box & CXA400.1 $382.99 Compatible with 2002-2009 GMC Envoy SUV Harmony R124 Single 12" Custom Sub... $235.99 Compatible with 2002-2009 GMC Envoy SUV Harmony A122 Single 12" Custom Sub... $305.99 2001-2006 GMC Sierra HD Crew Truck Harmony F104 Dual 10" Sub Box Enclosure New $239.99 01-06 GMC Sierra Non-HD Crew Cab Truck Harmony R104 Dual 10" Sub Box Enclosure $215.99 01-06 GMC Sierra Non-HD Crew Cab Truck Harmony F124 Dual 12" Sub Box Enclosure $264.99 Compatible with 2001-2006 GMC Sierra HD Crew Truck Harmony A102 Dual 10" Sub... $395.99 2001-2006 GMC Sierra HD Crew Truck Harmony R104 Dual 10" Sub Box & CXA400.1 Amp $323.99 2001-2006 GMC Sierra HD Crew Truck Harmony R104 Dual 10" Sub Box Enclosure New $225.99 1234567