Mounting Cutout Diameter (in). Mounting Cutout Diameter (mm). The item “JBL GTO939 6×9 3-Way Coaxial Car Speakers ORIGINAL (GTO 939) Shipping Fast” is in sale since Tuesday, October 10, 2017. This item is in the category “Consumer Electronics\Vehicle Electronics & GPS\Car Audio\Car Speakers & Speaker Systems”. The seller is “closeoutmartdeals” and is located in Buford, […]