This is a duplicate of sku BRN1855 (see csr note) - please don't set live, use sku BRN1855This is a duplicate of sku BRN1833 (see csr note) - please don't set live, use sku BRN1833One thing wasn't changed to make installation faster-everything was changed. From the unique telescoping mounting frame that fits through retrofit drywall openings without a need for attic access to this easy-to-insert snap-in blower and housing, This was designed the Ultra Series to be the fastest, easiest, most universal installation. Don't let the uncertainty of what's behind the drywall stand in your way. Take on any installation knowing that Ultra Series Ventilation Fans and Fan/Lights will make it easier and faster-up to 60% faster in retrofit installations and up to 20% faster in new construction. Because you don't make money by wasting time.