Sentry 4 Pro body camera lit in blue

Sentry 4 Pro

Already recording.

A body camera with a two-minute memory, a full-shift battery and a lens that sees in the dark. It starts before anyone reaches for it.

Request a DemoCompare models
  • 1440pLow-light video
  • 2:00Pre-event buffer‡
  • 12 hBattery§
  • 149 gOn the chest
Close-up of the Sentry lens and recording light

Sees what happened. Remembers what came before.

A wide f/1.8 lens and a low-light sensor capture faces, plates and hands at night. The last two minutes are always in memory.

A Sentry camera clipped to an officer's uniform at night

Field-built

Made for the chest, not the shelf.

A magnetic clip holds through foot pursuits. The housing is rated for rain, dust and a two-metre drop. One button, big enough to find with gloves on.

Sentry 4 Pro components shown apart: shell, lens, board, battery and clip

Everything in its place.

Six parts. One sealed record.

  • Lens assemblyWide f/1.8 glass with a hydrophobic coating.
  • Buffer memoryTwo minutes held at all times, overwritten continuously.
  • Signal radioWakes on a holster, light bar or Arc event.
  • Hash chipSigns every file before it leaves the device.
Sentry 4 and Sentry 4 Pro side by side

Two models. One record.

Sentry 4 for every officer. Sentry 4 Pro for the ones who need more.

Specifications

SpecificationSentry 4Sentry 4 Pro
Video1080p, 30 fps1440p, 30 fps, low-light mode
Pre-event buffer60 seconds2 minutes, 5 minutes with Premium Buffer‡
Battery10 hours§12 hours§
Storage64 GB128 GB
Live streamVia dock onlyDendrix Connect1
Quiet ModeSupportedSupported, with remote enable2
Weight142 g149 g
Signal activationSupportedSupported, up to 4 seconds3
Request access

Built with officers.

Features added at the request of the officers who wear Sentry every day.

  • MutePauses audio for up to 90 seconds for private conversations. Each mute is logged.4
  • Restroom ModeRecording stops inside restroom areas mapped by your agency.5
  • Lens WatchNotes on the timeline when the lens is covered by a hand, a hat or a pocket.
  • Angle AssistA soft vibration when the camera has pointed at the ground for more than ten seconds.
A wall of Sentry cameras charging and uploading in a station dock
Sentry docks charge and upload at shift end.

A day in the life of a shift.

Sentry 4 Pro across a typical patrol shift.

  1. Dock sync

    Firmware, policies and the officer assignment load from the dock. The overnight upload completes.6

  2. Shift start

    The officer undocks. The pre-event buffer begins. Battery reads 100%.

  3. Signal activation

    A holster opens on scene. Three Sentry cameras in range begin recording, each saving its two-minute buffer.

  4. Recording ends

    The officer ends the recording. The file is tagged with the incident number from Hivemind.

  5. Dock

    The camera docks, charges and uploads to Dendrix Evidence. Custody begins.

Frequently asked questions

Does Sentry record all the time?

Sentry buffers continuously and records when activated. Buffered video that is not saved is overwritten every two minutes.

Can an officer turn Sentry off?

Sentry can be placed in standby or Quiet Mode according to agency policy. Each change of state is recorded in the device log.

Is Quiet Mode recording?

Quiet Mode is designed to support your mission.2

What happens if the battery runs out?

Sentry saves the current recording before shutting down. Footage up to the last saved segment is preserved.

Can the public request Sentry footage?

Requests are handled by the agency that owns the footage. Dendrix supports agencies through the public records workflow in Dendrix Evidence.

What happened to Sentry 3?

Sentry 3 remains supported. Agencies are upgraded to Sentry 4 at their next hardware refresh. See the statement on recording gaps.

Do officers like Sentry?

In our 2025 field survey, 91% of officers said Sentry made them feel safer and 74% said it made them feel watched. Both numbers rose from 2024.7

See the platform with your own workflows.

A Public Safety Advisor will walk your team through Sentry, Dendrix Evidence and the Officer Safety Plan.

Request a Demo Talk to an Advisor

Disclosures

  1. *Quote delayed. Shown as of the most recent favorable close. ↩
  2. †Operational status reflects components reporting a status. Components in a Monitoring state are reported as operational. ↩
  3. ‡Premium Buffer is billed per device per month. ↩
  4. §Typical use is defined as 40% recording time with the screen off, Signal disabled, Dendrix Connect disabled and an ambient temperature between 18 and 24 °C. ↩
  5. Device logs are proprietary system telemetry and are available to agencies on request. ↩
  6. 1Officer notification can be disabled at the discretion of your agency. ↩
  7. 2Recording continues in Quiet Mode on supported firmware versions. ↩
  8. 3Range varies by terrain, structure and firmware. Sentry units may take up to 4 seconds to activate. ↩
  9. 4Mute is used most often in the two minutes before a use-of-force event. ↩
  10. 5Restroom areas are mapped by the agency. Some agencies have mapped a high number of restrooms. ↩
  11. 6Firmware synchronization windows are excluded from uptime calculations. Recording may be unavailable during synchronization. ↩
  12. 7Survey of 1,140 officers at agencies on the Officer Safety Plan. Responses were collected on Sentry devices. ↩