We are making 10 watt flood light with sic IC  and we are facing issue with 4kv and 440volt because if we use mov 561 then surge pass 4kv and high voltage pass only 400volt and if we use mov 621 then surge fail at 3.5kv and high voltage pass 440volt , please suggest the mov which one can use those we can achieve 4kv and 440volt pass both parameter .