Panasonic WhisperGreen Select Pick-A-Flow 50/80 or 110 CFM Exhaust Fan LED Light Flex-Z Fast bracket 4 or 6 in. duct adapter FV-0511VKL2 - The Home Depot
Panasonic FV-0511VHL1 WhisperWarm DC Bathroom Fan with Light and Heater - Simplified Ventilation and Heat - 50-80-110 CFM - Amazon.com
Panasonic FV-0811VFL5E WhisperFit EZ Retrofit Ventilation Fan with Light, 80 or 110 CFM - Amazon.com