HiLetgo SFM-27 95dB Alarm Buzzer: Wiring, Mounting, and Uses
The HiLetgo SFM-27 is a 95dB alarm buzzer that runs on 3 to 24V DC, 12V typical. Wire the red lead to positive and the black lead to ground, then bolt the mounting ears flat so the sound holes point out. The 5-pack costs $13.47 and suits alarms, RC builds, and electronics projects.
Quick facts
| Fact | Value |
|---|---|
| Sound | 95dB continuous beep |
| Voltage | 3 to 24V DC, 12V typical |
| Leads | Red positive, black ground |
| Mounting | Two ears with screw holes, bolts flat |
| Pack | 5 buzzers for $13.47 |
| Use | Alarms, lost-model beepers, warning buzzers |
What voltage does the SFM-27 need?
The SFM-27 runs on 3 to 24V DC, with 12V as the typical supply.
It sounds a 95dB continuous beep across that range, so it fits 5V, 12V, and 24V projects.
Wire the red lead to positive and the black lead to ground.
How do you mount the buzzer?
Bolt the buzzer flat through the screw hole in each mounting ear.
The white housing has sound holes on top, so mount it with the top clear and the sound pointing out.
Two ears hold it steady, which suits panels, cases, and RC frames.
How loud is 95dB in practice?
A 95dB beep carries across a room and a workshop, so it works as an alarm and a lost-model beeper.
The beep is continuous while power is applied, not pulsed.
Mount it clear of obstructions, because a blocked sound hole cuts the volume.
When do you pick the SFM-27 over a 5V FPV buzzer?
Pick the SFM-27 when your project runs above 5V or needs a panel-mounted alarm.
The 5V active buzzer solders to a flight controller and suits FPV quads, while the SFM-27 bolts to a case and suits alarms.
The SFM-27 5-pack costs $13.47, and the 5V buzzer 6-pack costs $7.49.
What did we check on the bench?
We checked the listing states 95dB, 3 to 24V, red and black leads, and mounting ears with screw holes.
We counted 3 images on the SFM-27 listing and 2 on the 5V buzzer listing.
We matched every price in this guide to the live store price on November 11, 2026.
How the options compare
| Buzzer | Sound | Voltage | Mounting | Price |
|---|---|---|---|---|
| HiLetgo SFM-27 5-pack | 95dB continuous | 3 to 24V DC | Screw ears, bolts flat | $13.47 |
| 5V active buzzer 6-pack | Beeps when driven | 5V | Solder to PDB or FC pads | $7.49 |
| JHE20B finder | 100dB alarm | 5V plus backup battery | Flight controller buzzer port | $8.97 |
How do you wire and mount the SFM-27?
- Pick a supply from 3 to 24V DC, 12V typical.
- Connect the red lead to positive and the black lead to ground.
- Bolt the mounting ears flat with the sound holes on top clear.
- Apply power and check the continuous beep.
- Fix the leads clear of moving parts before you close the case.
Parts that fit this guide
In-stock parts ship from the New York, USA warehouse in 1-2 business days. Prices below are the live store prices we verified on November 11, 2026.
HiLetgo SFM-27 95dB Alarm Buzzer, 3-24V, Continuous Beep, 5-Pack ($13.47)
HiLetgo SFM-27 5-pack at $13.47. It is a 95dB alarm buzzer on 3 to 24V DC with red and black wire leads and mounting ears.
5V Active Buzzer Beeper Tracker, 9 x 5.5mm, for FPV Racing Drone PDB Flight Controller, 6-Pack ($7.49)
5V active buzzer 6-pack at $7.49. It is a 9 by 5.5 mm buzzer that solders to PDB or flight controller pads.
Related parts: JHE Finder Buzzer with LED Alarm, 5V, 100-110dB (JHE20B / JHE42B / JHE42B-S): JHE finder buzzer, with a backup battery that sounds a 100 to 110dB alarm after power loss..
Shop the full range: FPV Accessories at Quality RC Parts. See also: Related guide.
Frequently asked questions
Does the SFM-27 beep on 5V?
Yes. It runs on 3 to 24V DC, so 5V is inside its range. 12V is the typical supply.
Is the beep continuous or pulsed?
Continuous. The buzzer sounds a steady 95dB beep while power is applied.
Can I use it as a lost-model beeper?
Yes. Mount it on the frame with the sound holes clear, and it works as a lost-model beeper or warning buzzer.
What is the difference from the 5V FPV buzzer?
The SFM-27 bolts to a case and runs on 3 to 24V. The 5V buzzer solders to a flight controller and runs on 5V only.
Sources
Last updated: November 11, 2026.