Expert Answers about Fiat Ducato

• Roof Vent to Fit 15 Inch x 15 Inch Roof Opening
• The 15" x 15" opening is standard for a 14" x 14" roof vent so something like the MaxxAir MaxxFan Mini Roof Vent w/ 12V Fan # MA00-04301M should fit just fine for your application (the garnish you have should measure 16" x 16"). If you'd like to try to reduce that hole a bit then there isn't a kit for that but you could try adding 1/2" shims around the opening to get the desired size.
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