New Dorman blower motor resistor.  This sits in the evaporator case on A/C models.  This controls the blower fan speed (as the switch does as well). Includes the connector also.  Fits the following:

82-92 Camaro w/ AC
82-92 Firebird/Trans Am w/ AC

TECH TIP : This resistor does not control the high speed, it only controls the lower 3 speeds, so if you don't have high speed, your problem is in the wiring, switch or high speed relay