Custom Exhaust fan curb adapters can be made to order. After we recieve an order we will confirm the dimensions.
 
Typical sizes vary from 21.5 (Base) x 19.5 (Cap) up to 44.5 (Base) x 38.5 (Cap) 
 
Does not include a hinge kit.
The adapter is 9" or 18" in height. 
The top of the Adapter will be 1.5" smaller than fan base size. 
The bottom of the Adapter will be 0.5" larger than your curb size. 
We recommend installing adapters with high temp silicone and 2 sheet metal screws on all sides for a tight fit.
 
NOTE: Adapters are a custom item and cannot be cancelled, returned, or exchanged once an order is placed.