The document details the STI Stopper II, a protective cover designed to prevent false fire alarms while allowing legitimate use, effective for over 30 years. It includes features such as polycarbonate construction for physical protection, an optional horn for alerts, and various models for indoor and outdoor applications. The product is UL listed, comes with a three-year guarantee against breakage, and is ideal for settings prone to false alarms like schools and hospitals.

1. FIRE PRODUCTS
For more information, call 1-800-888-4784 (4STI) or visit www.sti-usa.com
KEY features
General Information
· Proven effective for more than
30 years in helping stop false fire
alarms without restricting legitimate
alarms.
· Can be used as a guard against
physical damage to a manual pull
station, with or without the optional
warning horn.
· Protect devices such as EPOs, call
boxes, telephones and emergency
shutdowns by changing the color
and messaging.
· Three year guarantee against
breakage of polycarbonate in
normal use (one year on electro
mechanical and electronic
components).
Design
· Larger sizes and surface mounted
pull stations accommodated with
STI-3100 conduit spacer.
· Weather models have closed cell
gaskets.
· The Stopper II design is a registered
trademark of Safety Technology
International, Inc.
Construction
· UL Listed to U.S. and Canadian
safety standards (also for custom
labeling).
Installation
· When covering a pull station
outside, UL requires stations to be
listed for outdoor use.
· Typical working properties of
polycarbonate are -40° to 250°F
(-40° to 121°C).
Electronics
· Power source is a 9V DC alkaline
battery included on standard
Stopper II (remote powered unit
available).
· “RC” models include one Form “C”
dry relay contact and are capable
of operating from 9-24V DC remote
power or 9V DC battery power.
Options
· Optional horn has a choice of 95 or
105 dB at one foot.
· Standard red units have “In Case
of Fire...” label unless specified with
“no label” or “custom label” (extra
charge for custom label).
· Horn housing is available in red,
blue, green or yellow with optional
custom labeling.
Product Overview
This protective cover has been helping to stop false fire alarms around the world for
more than 30 years, without restricting legitimate alarms. All models offer excellent
protection against physical damage (both accidental and intentional) and several
against severe environments both inside and out. It is ideal for schools, colleges,
hospitals, nursing homes, stores, hotels and public buildings of almost every kind
where there is a threat of false alarms.
how it works
Stopper II consists of a clear, tamperproof, tough polycarbonate shield and frame, but
the line includes models with the option of a piezo horn, spacer, Form “C” dry relay
contact and gaskets. The cover accommodates most manual pull stations. When the
Stopper II with horn is lifted to gain access to the protected alarm, a piercing self-
contained 95 or 105 dB warning horn (at one foot) sounds. Immediate attention is
drawn to the area and a prankster will either run or be caught. The cover is connected
to the frame by a cable. When the cover is lifted, it drops off of the frame and a horn
will sound (models with horn) until the cover is snapped back onto the frame or for the
life of the battery.
STI Stopper II®
STI-1100
ADACompliant
ADACompliant
SEE REVERSE
FOR DETAILS
®

2. Printed in U.S.A., © 1987-2009 Safety Technology International, Inc.
2306 Airport Road
Waterford, Michigan
48327, USA
Tel: 248-673-9898
Fax: 248-673-1246
Toll-free: 800-888-4784
info@sti-usa.com
www.sti-usa.com
Unit 49G Pipers Road
Park Farm Industrial Estate
Redditch, Worcestershire
B98 OHU England
Tel: 44 (0) 1527 520 999
Fax: 44 (0) 1527 501 999
Free: 0800 085 1678 (UK)
www.sti-europe.com
04/11Subject to change without notice.Printed in U.S.A., © 1987-2009 Safety Technology International, Inc.
2306 Airport Road
Waterford, Michigan
48327, USA
Tel: 248-673-9898
Fax: 248-673-1246
Toll-free: 800-888-4784
info@sti-usa.com
www.sti-usa.com
Unit 49G Pipers Road
Park Farm Industrial Estate
Redditch, Worcestershire
B98 OHU England
Tel: 44 (0) 1527 520 999
Fax: 44 (0) 1527 501 999
www.sti-europe.com
04/11Subject to change without notice.
approvals warranty
TESTING
It has been tested and approved or listed by:
· UL/cUL Listed No. S2466
· For fire alarm applications, UL38 requires outdoor listed stations
for outdoor use
· Factory Mutual No. OG6A2.AY (STI-1100 and STI-1130 only)
· State of California (obtain local fire marshal approval)
· MEA 49-00-E (STI-1200)
· Flush models ADA Compliant. Surface models ADA Compliant
for operation (UL Certified No. S2466)
· IP44
· The indoor/outdoor rated station covers, when mounted on
a smooth surface, provide a rain tight seal similar to a 3R
enclosure rating.
WARRANTY
Three year guarantee against breakage of polycarbonate in
normal use (one year on electro mechanical and electronic
components).
STI Stopper II®
Dimensions and Technical Information
models available
Stopper II®
Models Indoor Use
STI-1100 With horn for flush mount
STI-1130 With horn and spacer
STI-1200 Without horn flush mount
STI-1230 Without horn with spacer
Weather Stopper®
with gaskets
(Indoor/Outdoor rated)
STI-1150 Stopper II with horn flush mount
STI-1155 Stopper II with horn and spacer
STI-1250 STI-1200 flush mount and gasket
STI-3150 STI-1200 with spacer and gaskets
Accessories
STI-3100 2” conduit spacer with 1/2” conduit entry (no
gaskets included)
STI-3104 2” conduit spacer with 3/4” conduit entry
(includes one 3/4” conduit entry gasket)
STI-1102 Replacement horn for cover with alarm
CUSTOM-LBL Custom text message for horn housing
STI-1280 Backplate for Stopper II and Weather Stopper
series important notice
Stopper II “FIRE” models are intended to be used in areas where
the incidence of false fire alarms from manual pull stations is high or
has proven to be a serious problem. Any disadvantage of this device
is more than balanced when one considers the consequences of
false fire alarms, especially if fire service personnel and equipment
are responding to a false fire alarm when they are needed for a real
fire somewhere else. Add to this the disruption to the facility when
false alarms occur. If you have, or may have, a problem with false
fire alarms or physical/weather damage to your fire alarm activation
devices, the Stopper II could prove invaluable.
*WARNING: ! For RC models: UL Listing does not permit relay
contacts to connect to the fire alarm or a life safety function.
The power supply for horns, according to UL Listing, cannot
be connected to a UL Listed fire alarm system. For electrical
specifications see install book. RC models contain one set of Form
“C” dry contacts. Contacts rated 30 VAC/VDC 1 amp.
EXTERNAL DIMENSIONS: • Flush 7.2 W x 10.2 H x 3.3 D in. (183x259x84mm)
• Surface 7.2 W x 10.2 H x 5.5 D in. (183x259x140mm)
SIDE VIEW
6.2 in.(158mm)
MODELS WITH HORN (STI-1100 Series)
COVER 5.5 in.(140mm)
8.5 in.(216mm)
3.2 in.(81mm)
2 in.(51mm)
SPACER
COVER 6.5 in.(165mm)
HORN HOUSING
3 in.(76mm)
ALL MODELS END VIEW
4 in.(102mm)
5 in.(127mm)
5.5 in.(140mm)
STI-3100 SPACER
ADDS 2 DEPTH(51mm)
5.5 in.(140mm)
E
.75 in.
(19mm)
1.625 in.
(41mm)
2.375 in.
(60mm)
2.75 in.
(70mm)
3.2 in.
(81mm)A
B
C
D
E
D
C
B
A
SURFACE MOUNT
WITH OPTIONS
K-OUT (2) PROVIDED
F CONDUIT IS NOT NEEDED
KET (USE WITH 1/2 in. CONDUIT)
KET (USE WITH 3/4 in. CONDUIT
SPACER)
CONDUIT SPACER
WITH SUB-316
OOR USE OR ADDITIONAL
ON DRILL 5 HOLES 1/8” DIAMETER
UNTING
SCREW WITH SPACER
OF RELAY CONTACT
SIDE VIEW
6.2 in.(158mm)
MODELS WITH HORN (STI-1100 Series)
COVER 5.5 in.(140mm)
8.5 in.(216mm)
3.2 in.(81mm)
2 in.(51mm)
ALL MODELS END VIEW
COVER
3.2 in.(81mm)
2 in.(51mm)5.5 in.(140mm)
5 in.(127mm)
3 in.(76mm)
SPACER
SPACER
SIDE VIEW
7.0 in.(178mm)
MODELS WITHOUT HORN (STI-1200 AND STI-3150 Series)
COVER 6.5 in.(165mm)
8.5 in.(216mm)
3.2 in.(81mm)
2 in.(51mm)
SPACER
HORN HOUSING
3 in.(76mm)
ALL MODELS END VIEW
4 in.(102mm)
5 in.(127mm)
5.5 in.(140mm)
STI-3100 SPACER
ADDS 2 DEPTH(51mm)
5.5 in.(140mm)
E
.75 in.
(19mm)
1.625 in.
(41mm)
2.375 in.
(60mm)
2.75 in.
(70mm)
3.2 in.
(81mm)A
B
C
D
E
D
C
B
A
STI-1280 BACKPLATE
*NOTE: STI SUGGESTS USING THE
STI-1280 BACKPLATE FOR WEATHER UNITS
OR WHEN MOUNTED ON AN UNEVEN SURFACE.
WALL
OPTIONAL STI-
RELAY BO
RED +9, 12
BLACK -9, 1
GREEN
WHITE
*
*
FOR RETROFIT APPLICATIONS,
CUT GASKET AT THE BOTTOM TO
INSTALL BEHIND CONDUIT
SPACER
SPACER
COVER
COVER
HORN HOUSING
8.875 in.
(225mm)
6 in.
(152mm)
5.37 in.
(137mm)
8.875 in.
(225mm)
7.4 in.
(188mm)
5.34 in.
(136mm)
2 in.
(51mm)
.5 in.
(13mm)
3.175 in.
(81mm)
1 in.
(25mm)
3.175 in.
(81mm)
2 in.
(51mm)
.78 in.
(20mm) SPACER ADDS
2” DEPTH (50mm)
3 in.
(76mm)
4 in.
(102mm) 5 in.
(127mm)5.5 in.
(140mm)
6.81 in.
(173mm)
1.61 in.
(41mm)
2.32 in.
(59mm)
2.73 in.
(70mm)
3.18 in.
(81mm)
7.23 in.
(184mm)
10.07 in.
(256mm)
SPACER
SPACER
COVER
COVER
HORN HOUSING
8.875 in.
(225mm)
6 in.
(152mm)
5.37 in.
(137mm)
8.875 in.
(225mm)
7.4 in.
(188mm)
5.34 in.
(136mm)
2 in.
(51mm)
.5 in.
(13mm)
3.175 in.
(81mm)
1 in.
(25mm)
3.175 in.
(81mm)
2 in.
(51mm)
.78 in.
(20mm) SPACER ADDS
2” DEPTH (50mm)
3 in.
(76mm)
4 in.
(102mm) 5 in.
(127mm)5.5 in.
(140mm)
6.81 in.
(173mm)
1.61 in.
(41mm)
2.32 in.
(59mm)
2.73 in.
(70mm)
3.18 in.
(81mm)
SIDE VIEW
6.2 in.(158mm)
MODELS WITH HORN (STI-1100 Series)
COVER 5.5 in.(140mm)
8.5 in.(216mm)
3.2 in.(81mm)
2 in.(51mm)
ALL MODELS END VIEW
COVER
3.2 in.(81mm)
2 in.(51mm)5.5 in.(140mm)
5 in.(127mm)
3 in.(76mm)
SPACER
SPACER
SIDE VIEW
7.0 in.(178mm)
MODELS WITHOUT HORN (STI-1200 AND STI-3150 Series)
COVER 6.5 in.(165mm)
8.5 in.(216mm)
3.2 in.(81mm)
2 in.(51mm)
SPACER
HORN HOUSING
3 in.(76mm)
ALL MODELS END VIEW
4 in.(102mm)
5 in.(127mm)
5.5 in.(140mm)
STI-3100 SPACER
ADDS 2 DEPTH(51mm)
5.5 in.(140mm)
E
.75 in.
(19mm)
1.625 in.
(41mm)
2.375 in.
(60mm)
2.75 in.
(70mm)
3.2 in.
(81mm)A
B
C
D
E
D
C
B
A
STI-1280 BACKPLATE
*NOTE: STI SUGGESTS USING THE
STI-1280 BACKPLATE FOR WEATHER UNITS
OR WHEN MOUNTED ON AN UNEVEN SURFACE.
WALL
OPTIONAL ST
RELAY B
RED +9, 1
BLACK -9,
GREEN
WHI
*
*
FOR RETROFIT APPLICATION
CUT GASKET AT THE BOTTOM T
INSTALL BEHIND CONDU