| PartNumber | PFD-27N35WQ | PFD-21A29WQ | PFD-20A35EWQ |
| Description | Audio Indicators & Alerts CONSTANT/FAST PULSE 3.5KHZ, 90DB, 30X16 | Audio Indicators & Alerts CONSTANT/FAST PULSE 3-24VDC, 85DB, 24X14 | Audio Indicators & Alerts CONSTANT/FAST PULSE 3-24VDC, 95DB, 28X25 |
| Manufacturer | Mallory Sonalert | Mallory Sonalert | Mallory Sonalert |
| Product Category | Audio Indicators & Alerts | Audio Indicators & Alerts | Audio Indicators & Alerts |
| RoHS | Y | Y | Y |
| Product | Buzzers | Buzzers | Buzzers |
| Sound Pressure Level | 90 dBA | 85 dBA | 95 dBA |
| Tone | Continuous | Continuous | Continuous |
| Voltage Rating | 12 V | 12 V | 12 V |
| Current Rating | 15 mA | 18 mA | 10 mA |
| Termination Style | Wire Leads | Wire Leads | Wire Leads |
| IP Rating | - | - | - |
| Diameter | 30 mm | 24 mm | 28 mm |
| Dimensions | 30 mm L x 30 mm W x 16 mm H | 24 mm L x 24 mm W x 13.5 mm H | 28 mm L x 28 mm W x 25 mm H |
| Mounting | Flush | Flush | Flange |
| Height | 16 mm | 13.5 mm | 25 mm |
| Length | 30 mm | 24 mm | 28 mm |
| Series | PFD | PFD | PFD |
| Width | 30 mm | 24 mm | 28 mm |
| Brand | Mallory Sonalert | Mallory Sonalert | Mallory Sonalert |
| Height in | 0.63 in | 0.551 in | 0.984 in |
| Height mm | 16 mm | 14 mm | 25 mm |
| Product Type | Audio Indicators & Alerts | Audio Indicators & Alerts | Audio Indicators & Alerts |
| Factory Pack Quantity | 1 | 1 | 1 |
| Subcategory | Audio Devices | Audio Devices | Audio Devices |
| Unit Weight | 0.275137 oz | 0.126986 oz | 0.345685 oz |
| Frequency | - | - | 3.5 kHz |