| PartNumber | HRISW25B | HRISW27I | HRISW21FT |
| Description | Time Delay & Timing Relays TIMEDELAYRELAY | Time Delay & Timing Relays TIMEDELAYRELAY | Time Delay & Timing Relays TIMEDELAYRELAY |
| Manufacturer | Littelfuse | Littelfuse | Littelfuse |
| Product Category | Time Delay & Timing Relays | Time Delay & Timing Relays | Time Delay & Timing Relays |
| RoHS | Y | Y | Y |
| Display Type | Analog Dial | Analog Dial | Analog Dial |
| Termination Style | Quick Connect Terminal | Quick Connect Terminal | Quick Connect Terminal |
| Relay Contact Form | 1 Form C (SPDT-NO, NC) | 1 Form C (SPDT-NO, NC) | 1 Form C (SPDT-NO, NC) |
| Timing Range | 1 m to 100 m | 0.1 s to 10 h | 0.1 s to 10 s |
| Series | HRIS | HRIS | HRIS |
| Packaging | Bulk | Bulk | Bulk |
| Contact Form | SPDT (1 Form C) | SPDT (1 Form C) | SPDT (1 Form C) |
| Brand | Littelfuse | Littelfuse | Littelfuse |
| Product Type | Timing Relays | Timing Relays | Timing Relays |
| Factory Pack Quantity | 1 | 1 | 1 |
| Subcategory | Relays | Relays | Relays |