---
product_id: 8938632
title: "SM-226L-3Q Overhead Door Magnetic Contact, 2.75-inch Gap, Open/Closed Loop Circuits (3 Wires), 24\" Armored Wire Leads, Weatherproof"
brand: "seco-larm"
price: "$48.14"
currency: USD
in_stock: true
reviews_count: 8
category: "Seco Larm"
url: https://www.desertcart.us/products/8938632-sm-226l-3q-overhead-door-magnetic-contact-2-75-inch
store_origin: US
region: United States of America
---

# Durable under heavy vehicle pressure Designed for large doors & gates Powerful magnet for secure contact SM-226L-3Q Overhead Door Magnetic Contact, 2.75-inch Gap, Open/Closed Loop Circuits (3 Wires), 24" Armored Wire Leads, Weatherproof

**Brand:** seco-larm
**Price:** $48.14
**Availability:** ✅ In Stock

## Summary

> 🛡️ Seco-Larm: The heavy-duty guardian your doors deserve

## Quick Answers

- **What is this?** SM-226L-3Q Overhead Door Magnetic Contact, 2.75-inch Gap, Open/Closed Loop Circuits (3 Wires), 24" Armored Wire Leads, Weatherproof by seco-larm
- **How much does it cost?** $48.14 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/8938632-sm-226l-3q-overhead-door-magnetic-contact-2-75-inch)

## Best For

- seco-larm enthusiasts

## Why This Product

- Trusted seco-larm brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Versatile Mounting:** L-shaped bracket and door mount design for seamless installation on large doors and gates.
- • **Optimized Dimensions:** Compact 9 x 5.5 x 2 inches size fits large doors without bulk or compromise.
- • **Unmatched Durability:** Withstands heavy vehicle pressure without damage—built tough for high-traffic entryways.
- • **Premium Build Quality:** Gray ABS case with aluminum material for long-lasting performance and weather resistance.
- • **Reliable Contact Switch:** NO/NC contact switch ensures precise security monitoring and flexible integration.

## Overview

Seco-Larm is a robust door magnet sensor housed in a gray ABS case with an L-shaped bracket, engineered for large doors and gates. Featuring a NO/NC contact switch and aluminum construction, it withstands heavy vehicle pressure, ensuring reliable security and durability in demanding environments.

## Description

The Seco-Larm Enforcer Overhead Door-Mount Magnetic Contact, NO/NC is a contact switch designed for large doors and gates where regular contacts may be difficult to mount. The contact’s large gap allows use with even the largest doors, such as garage doors. The switch is contained in low-profile cast aluminum housing, and curved so that heavy vehicles can cross over without damaging it.NO/NC contact switchUse on large doors or gatesMagnet in gray ABS case mounted on L-shaped bracket24-inch wire leads enclosed in stainless-steel cableRugged, Long-Lasting ConstructionSeco-Larm contacts have a unique rhodium plating which has gone through a special oxygen treatment to deactivate the surface, thus eliminating the absorption of organic impurities, polymer growth during operation, and the possibility of contact freezing.The switch is housed in weatherproof die-cast aluminum constructed for surface-mounting on a garage floor. It can withstand heavy vehicle pressure without damage. The switch is safely enclosed in an epoxy compound, and a 24-inch flexible stainless-steel cable gives complete protection to the switch wiring.The magnet is housed in a high-impact weatherproof ABS plastic case and can be mounted on a garage door with an "L"-shaped bracket, which minimizes the effect of steel doors on magnets.Technical DetailsMPN: SM-226L-3QUPC: 676544006473Alarm circuit: Three-wire N.O./N.C. Contact for either closed or open circuit alarm systemsReed switch: Gold under-plating with deactivated rhodium outer-platingSwitch housing: Weatherproof die-cast aluminumMagnet: Extra-strength Alnico 5Wire: 24 inches (61 cm), stainless-steel enclosureContact lifetime: 50 million cyclesRating: 0.02Amp./100VDC (max.), 0.2Amp./10VDC (max.), 3W (max.)Temperature: -15 to 160 °F (-25 to 70 °C)Dimensions: 4-3/8 x 1-3/4 x 7/16 inches (111 x 44 x 11 mm)Gap: 2-3/4 inches (70 mm)Listings: UL, RoHS

Review: This is the way these things should all be - This is a great switch. The switch part is both lightweight and extremely tough; the magnet part is easy to mount and also light. The activation distance is around two inches that makes for finding a nice mount point easy. Additionally, the magnet can be reversed on the mount if you need a little more distance for a weird mounting spot. The armored cable protects the signal wires, so if you run over it with the car it will still work. Since it has normally open and normally closed outputs, it will work in any wired alarm application. Really nice device.
Review: Works anywhere you need a magnetic sensors. - Use this on a sliding driveway gate. My limit switch system was a gear moving along a threaded rod that pushes a shut off switch. With seasonal changes this requires the limits to the reset. It was a hassle to adjust. When the old limit switch system finally gave after 20 years of service it was going to cost $300 to replace. I've decided to use this instead since I can mount the magnets to the slider gate and the magnetic sensors to the motor brackets. Worked like a charm no adjusting for seasonal changes. I've saved $260 by using this a limit switches.

## Features

- Magnet in gray ABS case mounted on L-shaped bracket
- Use on large doors (garage) or gates
- NO/NC contact switch
- Withstands heavy vehicle pressure without damage

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B005H3GCW0 |
| Best Sellers Rank | #227 in Home Security Systems |
| Brand Name | Seco-Larm |
| Color | Gray |
| Customer Reviews | 4.6 4.6 out of 5 stars (269) |
| Finish Types | Unfinished |
| Item Depth | 9 inches |
| Item Dimensions | 9 x 5.5 x 2 inches |
| Manufacturer | Seco-Larm |
| Manufacturer Part Number | SM-226L-3Q |
| Material Type | Aluminum |
| Model Number | SM-226L-3Q |
| Mounting Type | Door Mount |
| UPC | 676544006473 |
| Unit Count | 1 Count |

## Product Details

- **Brand:** Seco-Larm
- **Color:** Gray
- **Finish Type:** Unfinished
- **Item dimensions L x W x H:** 9 x 5.5 x 2 inches
- **Material:** Aluminum

## Images

![SM-226L-3Q Overhead Door Magnetic Contact, 2.75-inch Gap, Open/Closed Loop Circuits (3 Wires), 24" Armored Wire Leads, Weatherproof - Image 1](https://m.media-amazon.com/images/I/41d93LTq96L.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ This is the way these things should all be
*by D***N on February 12, 2016*

This is a great switch. The switch part is both lightweight and extremely tough; the magnet part is easy to mount and also light. The activation distance is around two inches that makes for finding a nice mount point easy. Additionally, the magnet can be reversed on the mount if you need a little more distance for a weird mounting spot. The armored cable protects the signal wires, so if you run over it with the car it will still work. Since it has normally open and normally closed outputs, it will work in any wired alarm application. Really nice device.

### ⭐⭐⭐⭐⭐ Works anywhere you need a magnetic sensors.
*by C***I on June 4, 2025*

Use this on a sliding driveway gate. My limit switch system was a gear moving along a threaded rod that pushes a shut off switch. With seasonal changes this requires the limits to the reset. It was a hassle to adjust. When the old limit switch system finally gave after 20 years of service it was going to cost $300 to replace. I've decided to use this instead since I can mount the magnets to the slider gate and the magnetic sensors to the motor brackets. Worked like a charm no adjusting for seasonal changes. I've saved $260 by using this a limit switches.

### ⭐⭐⭐⭐⭐ Good products
*by K***R on July 8, 2025*

Works as it should.

## Frequently Bought Together

- Seco-Larm SM-226L-3Q Overhead Door Magnetic Contact, 2.75-inch Gap, Open/Closed Loop Circuits (3 Wires), 24" Armored Wire Leads, Weatherproof
- Seco-Larm SM-4601-L3Q Industrial Wide-Gap Magnetic Contact Switches, 3" Operation Gap NO/NC, Open/Closed Loop (3 Wires)
- Seco-Larm SM-4201-LQ Track-Mount Overhead Door Magnetic Contact Switch, Rugged Aluminum Housing, 36" Wire Leads, for Closed Loop Circuits, 3" Gap, Weatherproof, Mounting Bracket Included

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*Product available on Desertcart United States of America*
*Store origin: US*
*Last updated: 2026-07-06*