| 501 | 621-1100 | Honeywell | Honeywell 621-1100 115V AC / DC Input | instock |
| 502 | 621-1101 | Honeywell | Honeywell 621-1101 115V AC / DC Isolated Input 6 Point | instock |
| 503 | 621-1101R | Honeywell | Honeywell 621-1101R | instock |
| 504 | 621-1101RC | Honeywell | Honeywell 621-1101RC | instock |
| 505 | 621-1150 | Honeywell | Honeywell 621-1150 115V AC Input | instock |
| 506 | 621-1151 | Honeywell | Honeywell 621-1151 115V AC Input | instock |
| 507 | 621-1160 | Honeywell | Honeywell 621-1160 16 Point 115V AC Input | instock |
| 508 | 621-1160R | Honeywell | Honeywell 621-1160R | instock |
| 509 | 621-1175 | Honeywell | Honeywell 621-1175 115V AC Input | instock |
| 510 | 621-1180 | Honeywell | Honeywell 621-1180 32 Point 115V AC Input | instock |
| 511 | 621-1200 | Honeywell | Honeywell 621-1200 230V AC / DC Input | instock |
| 512 | 621-1200RC | Honeywell | Honeywell 621-1200RC | instock |
| 513 | 621-1201 | Honeywell | Honeywell 621-1201 230V AC / DC Isolated Input 6 Point | instock |
| 514 | 621-1250 | Honeywell | Honeywell 621-1250 16 Point 240V AC Input | instock |
| 515 | 621-1250R | Honeywell | Honeywell 621-1250R | instock |
| 516 | 621-1251 | Honeywell | Honeywell 621-1251 16 Point 240V AC Input Isolated | instock |
| 517 | 621-1500 | Honeywell | Honeywell 621-1500 24V AC Input | instock |
| 518 | 621-1550 | Honeywell | Honeywell 621-1550 24V AC Input | instock |
| 519 | 621-2100 | Honeywell | Honeywell 621-2100 230V AC Output | instock |
| 520 | 621-2101 | Honeywell | Honeywell 621-2101 115V AC Isolated Output 6 Point | instock |
| 521 | 621-2101R | Honeywell | Honeywell 621-2101R | instock |
| 522 | 621-2101RC | Honeywell | Honeywell 621-2101RC | instock |
| 523 | 621-2102 | Honeywell | Honeywell 621-2102 115V AC Output Self Protected | instock |
| 524 | 621-2150 | Honeywell | Honeywell 621-2150 115V AC Output | instock |
| 525 | 621-2150R | Honeywell | Honeywell 621-2150R | instock |
