ActronAir Indoor Evaporator Fan Deck 9x9 T 600W is the T-configuration 9x9 fan deck for Classic Series residential ducted systems where the T-mount shaft orientation positions the motor on the opposite side to the standard S-configuration for housing layouts that require this arrangement. Fitting an S-configuration deck in a T-mount housing reverses airflow direction and causes immediate system failure -- always confirm the configuration designation before ordering. Isolate power at mains before replacement -- live work on fan assemblies is dangerous and must only be performed by a qualified technician.