| Inline-direct drive, VariGreen EC, insulation, 2HP 208V/1ph | $3,763.00 | | |
| Integrated CO2 Sensor, For Models SP-AP0511W and SP-AP0511WL | $132.00 | | |
| Integrated Dehumidistat, For Models SP-AP0511W and SP-AP0511WL | $114.00 | | |
| Internal Actuator Kit, Multi Products, MP-100 Act, 115-230V, 50/60HZ, for WD-100 Series, Product # 826840 | $149.00 | | |
| Internal Actuator Kit, Multi Products, MP-100 Act, 24V, 60HZ, for WD-100 Series, Product # 826848 | $273.00 | | |
| Internal Actuator Kit, Multi Products, MP-100 Act, 460V, 60Hz, for WD-100 Series, Product # 826844 | $163.00 | | |