Filter Filters GMC Remove All Filters Price $100-$500 (54) $500 and above (1) Condition New (55) Brand Harmony Audio (55) Model Sierra (51) Canyon (2) Envoy (1) Sonoma (1) Compatible with 2001-2006 GMC Sierra 1500 Crew Truck Harmony R104 Ported 10"... $216.99 Compatible with 2007-2013 GMC Sierra Extended Cab Truck Harmony A102 Single... $399.99 Compatible with 1988-1998 GMC Sierra Extended Cab Truck Harmony A102 Single... $310.99 2007-2013 GMC Sierra Crew Cab Truck Harmony R124 Dual 12" Sub Box & CXA400.1 Amp $386.99 Compatible with 2007-2013 GMC Sierra Crew Cab Truck Harmony R124 Dual 12" Sub... $336.99 Compatible with 2007-2013 GMC Sierra Crew Cab Truck Harmony A102 Dual 10" Sub... $499.99 Compatible with 2007-2013 GMC Sierra Crew Cab Truck Harmony A102 Dual 10" Sub... $424.99 2007-2013 GMC Sierra Extended Cab Truck Harmony R104 Single 10" Loaded Sub... $281.99 Compatible with 2007-2013 GMC Sierra Extended Cab Truck Harmony R104 Single... $236.99 Compatible with 2007-2013 GMC Sierra Extended Cab Truck Harmony A102 Single... $324.99 Compatible with 2007-2013 GMC Sierra Extended Cab Truck Harmony A122 Dual 12"... $395.99 Compatible with 2004-2014 GMC Canyon Crew Cab Truck Harmony F104 Dual 10" Sub... $405.99 Compatible with 2007-2013 GMC Sierra Extended Cab Truck Harmony R124 Dual 12"... $312.99 Compatible with 2007-2013 GMC Sierra Crew Cab Truck Harmony R104 Dual 10" Sub... $308.99 Compatible with 2001-2006 GMC Sierra HD Crew Truck Harmony R124 Dual 12" Sub... $326.99 Compatible with 1999-2006 GMC Sierra Extended Cab Truck Harmony A102 Single... $325.99 Compatible with 01-06 GMC Sierra Non-HD Crew Cab Truck Harmony R104 Dual 10"... $310.99 Compatible with 2007-2013 GMC Sierra Crew Cab Truck Harmony F104 Dual 10" Sub... $479.99 Compatible with 1999-2006 GMC Sierra Extended Cab Truck Harmony R104 Single... $246.99 Compatible with 1988-1998 GMC Sierra Extended Cab Truck Harmony A102 Dual 10"... $394.99 Compatible with 1988-1998 GMC Sierra Extended Cab Truck Harmony R104 Single... $236.99 Compatible with 2001-2006 GMC Sierra HD Crew Truck Harmony F104 Dual 10" Sub... $410.99 Compatible with 2007-2013 GMC Sierra Crew Cab Truck Harmony F104 Dual 10" Sub... $404.99 Compatible with 1988-1998 GMC Sierra Extended Cab Truck Harmony F104 Dual 10"... $399.99 123