# Door sensor BLOW 4920# magnetic reed contact HO-03B brown

**URL:** https://aio.lv/en/product--blow-4920--11863680
**Data updated:** 2026-03-09 17:40 (EET)
**Category:** Smart Sensors
**Manufacturer:** BLOW
**Manufacturer code:** 4920#
**EAN:** 5900804098911
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 5.99 €
**Prices and availability valid until:** 2026-07-18 23:59
**Price without VAT (21%):** 4.95 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--blow-4920--11863680

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 13.07.2026 | free |
| Pickup points | 16.07.2026 | 1.99 EUR |
| Courier delivery to door | 16.07.2026 | 4.99 EUR |

## Summary description

Magnetic door sensor BLOW 4920# (HO-03B) in brown. A reed-contact type door/window sensor designed for intrusion detection and alarm systems. Consists of a magnet and a switch that closes or opens the circuit when the door or window moves; suitable for mounting on frames for basic contact detection in residential or commercial alarm installations.

## Long description

Magnetic door sensor BLOW 4920# (HO-03B) in brown is a reed-contact type sensor intended for basic door and window contact detection in intrusion and alarm systems. The device comprises a magnet and a magnetic switch that change state when the relative position between the two parts is altered. Its compact brown housing is designed for discreet surface mounting on frames and sashes in residential and commercial installations.
Advantages
The reed-contact design provides simple and reliable open/close detection without requiring power at the sensor itself, reducing installation complexity. The small form factor and neutral brown finish allow unobtrusive placement on wooden or painted frames. Mechanical simplicity supports long service life and low maintenance needs, while the sensor is compatible with a wide range of alarm control panels that accept normally open or normally closed reed contacts.
Suitable for
Basic intrusion detection on doors and windows
Residential alarm systems where discreet appearance is required
Commercial premises for perimeter contact monitoring
Retrofit installations on existing frames and sashes
Key specifications
Type: Reed (magnetic) contact sensor
Function: Open/close contact for alarm input
Mounting: Surface mount on frame and sash
Colour: Brown housing for visually discrete installation
Construction: Two-part magnet and switch assembly
How to use
Position the switch body on the fixed frame and the magnet on the moving sash so that the two parts align when the door or window is closed. Secure both parts with screws or adhesive as appropriate for the mounting surface, ensuring the correct gap and alignment specified by the alarm system manufacturer. Connect the sensor leads to the alarm control panel input, observing the required wiring configuration for normally open or normally closed circuits. Test the sensor operation with the control panel to verify correct state change when the door or window is opened and closed.
Usage recommendations
For reliable performance, mount the sensor away from heavy vibration sources and metal elements that could affect magnetic operation. Use compatible screws or suitable adhesive for the installation surface, and verify contact alignment after door or window adjustments. Periodically test the contact state as part of routine alarm system maintenance.

## FAQ

### How much does the Door sensor BLOW 4920# HO-03B cost, and is it available for purchase?

The price is 5.99 € (valid at the time of publication and already includes all taxes). The item is available for order — 86 pcs. are in stock, and you can place your purchase right now with delivery across Latvia and Europe or choose pickup at the Riga collection point. We offer favorable purchase terms, including the option to split the payment into convenient monthly installments. Availability and price are updated in real time, so we recommend placing your order in advance.

### If I order this product today, when will I receive my order?

If you place your order today, delivery will be as fast and convenient as possible. You will be able to pick up your order on 13.07.2026 at the Riga pickup point or choose delivery across Latvia and Europe. We carefully inspect every purchase and pack it securely for safe transportation.

### What payment options are available?

AiO.lv offers several payment methods: Bank transfer, Bank cards on-line, Apple Pay, Google Pay. All transactions are 100% secure and encrypted.

### Can this product be purchased for a company (with VAT)?

Yes. AiO.lv works with legal entities in Latvia and across Europe. The product price already includes VAT. For certain product categories, as well as for companies from other EU countries with a valid VAT number, a 0% VAT rate may apply. We issue the invoice immediately after the order is placed, support electronic BIS invoices, and automatically generate all necessary accounting documents. You can complete the purchase for a company online — simply select the company profile and choose bank transfer as the payment method during checkout.

### What is the warranty period?

All BLOW products come with an official 2 Years warranty. It covers all manufacturing defects and malfunctions that may occur during use. The warranty is valid at all authorized BLOW service centers and through AiO.lv

### Can the product be returned after purchase?

Yes, you can return the product within 14 days of purchase if you bought it as a consumer (not a legal entity). Returns are possible without giving any reason — the main condition is that the product retains its original appearance and full set of accessories. We will make the process as simple and convenient as possible: just contact our customer support team, and we will help you arrange the return.

### Where should I contact for warranty service?

For warranty-related questions you can contact the AiO.lv (SIA VSPRO) customer support team. More information about warranty service: https://aio.lv/en/warranty

## Image

https://aio.lv/img/cache/product/11863680/67262331_large.webp