Adapter curbs offer many advantages. Roof top air conditioning equipment can be changed out quickly without affecting the building envelope and eliminates modifications to the existing curb and ductwork. KCC adapters are available for units from 2 to 130 tons. Our extensive database of air conditioning equipment includes most brands and models manufactured in the past 30 years. We have thousands of ready-to-manufacture adapter designs in our database, many of which can be built and shipped as quickly as next business day.