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STI 6400 Exit Stopper Door Alarm - For Single Doors

Red sti exit stopper with alarm speaker, warning text, keys, mounting brackets, screws, and a key tag on a white background
Red sti exit stopper with alarm speaker, warning text, keys, mounting brackets, screws, and a key tag on a white background Front view of a red sti exit stopper showing the word STOP and speaker symbols Side view of red sti exit stopper showing its smooth surface and rectangular shape Back view of a red sti exit stopper showing its flat surface and central screw Red sti exit stopper shown from an angled view with speaker holes and key lock visible Close up of red sti exit stopper angled showing speaker holes and part of warning text alarm will sound sti exit stopper showing a close-up of a silver keyhole on a red surface Close-up of the red sti exit stopper showing the speaker area with sound wave symbol STI-6400 Exit Stopper Door Alarm With Contents Red sti exit stopper device with keyhole and matching box showing product images and text
4.8 out of 5 stars

20+ In Stock

For dispatch today order within
4 Hrs 37 Mins
£106.50 inc VAT

£94.50 inc VAT

£78.75 ex VAT

Standard Delivery

Will usually be delivered in 2-3 working days

£4.20 inc VAT

Next Day Delivery

Will usually be delivered the next working day

£7.00 inc VAT

The STI-6400 Exit Stopper is a compact, self‑contained fire exit door alarm designed to provide an immediate audible warning when an emergency exit door is opened. Ideal for schools, retail premises, and public buildings, this highly visible alarm acts as a powerful deterrent against unauthorised use and vandalism.

  • Designed for single emergency exit doors
  • Ideal for retrofit door security – quick and easy installation
  • Simple installation with no additional wiring required
  • Actively discourages acts of vandalism and unauthorised use of the door
  • Loud 95dB / 105dB alarm – immediately alerts nearby staff
  • Capable of being battery operated or mains powered with battery back-up
  • Highly visible bright red casing with 'STOP' text for maximum deterrence
  • Silence and reset alarm with key-operated manual override
  • User programmable alarm duration and delays using the internal DIP switches
  • Manufactured in the UK
  • Warranty under normal use:
    • 3 years – breakage of polycarbonate
    • 1 year – electro-mechanical and electronic components
  • Also available for double door applications
Customer Reviews

Customer Reviews (21)

4.8 out of 5 stars

Reviews by Real Customers

All of our product reviews are written by real customers that have purchased this product from us and are published without modification.

Rating: 5 / 5

Reviewer

D N

Great product and delivery

Published on

29th August 2023

Rating: 5 / 5

Reviewer

T S

Does exctly what it says on the tim

Published on

13th March 2023

Rating: 4 / 5

Reviewer

K L

Good product

Published on

10th September 2021

FAQs

FAQs (4)

Is there a battery-operated device that can be used to sound in the event of a fire exit door being opened?

The Exit Stopper Door Alarm, available for single or double doors, is battery operated and sounds when a fire exit door is opened. It is designed with magnet contacts, and when the contact is broken it sounds a loud 97dB alarm. A key override is fitted to reset and to manually override the alarm to allow the door to be used normally, or for maintenance.

Can remote sounders be fitted to a fire door that requires monitoring?

Yes, the Exit Stopper can connect to remote sounders via a cable. There are no restrictions on the distance between them.

Does the Exit Stopper stop sounding if the fire exit door that has been opened is closed again?

Yes, the Exit Stopper has several reset functions. One of these is that the alarm will reset once the door has been closed again.

Can the Exit Stopper be turned off to allow the use of a fire exit door at certain parts of the day?

Yes, the Exit Stopper can be manually overridden by the supplied key to allow for the fire exit door to be used as a normal door at certain parts of the day.

Technical Data

Technical Data

Product Code ST6400
Brand STI EMEA
Manufacturer's Part Number STI-6400
Battery Type 9V Battery
Alkaline
Colour Red
Equipment Type Door Alarm / Sounder
Fixing Options Screws (included)
Manufactured in the UK Yes
Material Polycarbonate
Operating Temperature 0°C To +45°C
Power Type Battery Powered
Switchable (12V / 24V DC)
Recyclable Partially Recyclable
Security Features Alarm
Sound Level 97dB
Warranty 1 Year (Electronic Components)
3 Years (Polycarbonate Housing)
Dimensions (Unit)
  • Height: 136mm
  • Width: 136mm
  • Depth: 50mm
Weight 500g
Datasheets
Front view of a red exit stopper for double doors with stop warning and speaker grill visible

STI 6402 Exit Stopper Door Alarm - For Double Doors

£155.24 inc VAT

£129.37 ex VAT

 angled view of multiguard 6 way indicator individual silence reset showing buttons and labelled zones

Multiguard 6 Way Indicator with Individual Silence and Reset

From: £464.99 inc VAT

£387.49 ex VAT

 a contents shot of what is included in the exit stopper remote installation kit

Exit Stopper Remote Installation Kit - STI 6400/RK

£23.95 inc VAT

£19.96 ex VAT

 Two exit stopper replacement keys shown angled up with visible cut edges and number 2841 engraved

Spare Keys for STI Exit Stopper Alarms

£9.35 inc VAT

£7.79 ex VAT

 angled view of multiguard 6 way indicator global silence reset device with labelled buttons and display panel

Multiguard 6 Way Indicator with Global Silence and Reset

From: £323.39 inc VAT

£269.49 ex VAT

 Front view of red exit stopper remote sounder showing speaker and sensor details

Exit Stopper Remote Sounder STI6400/RS

£70.15 inc VAT

£58.46 ex VAT