※ This is a single item listing, but there are 5 in stock. If you wish to purchase multiple units, we will discount the shipping cost, so please let us know. This is an ABH-250L 4-beam infrared beam sensor made by the overseas security equipment manufacturer Alean. It supports outdoor surveillance up to a distance of 250M. The 2-digit digital display allows you to adjust the sensitivity from 0 to 99, allowing for light axis adjustment without the need for an electrical tester. I have been using it for about six months, and if the adjustment is done properly, there have been no false alarms, and the reliability is comparable to domestic products. Although it is in English, if you have used beam sensors before, the basics are the same as other companies' products, so you should be able to handle it easily. Support is available if you have any questions. Accessories include the instruction manual, pole brackets, and mounting screws. -Features- 1. NC/NO relay output, compatible with alarm systems from other brands such as Honeywell, Bosch, Paradox, DSC, and GE. 2. Digital filter technology provides excellent performance against direct sunlight, fluorescent lights, and car lights. 3. Built-in tamper switch, which activates when the cover is moved. 4. Different frequencies can be selected for long-distance and stacking installations. 5. Signal grade is displayed with LEDs for easy alignment. 6. Wide voltage range and energy-saving design. 7. Adjustable interruption time (50/100/300/700 milliseconds options). 8. IP65 waterproof rating. 9. Alignment angle is horizontal ±90°, vertical ±10°. 10. RFI interference prevention and high environmental adaptability eliminate false alarms. Manufacturer product information ↓ http://www.alean.com.cn/products_more.asp?id=2803&cl_na=Perimeter%20Infrared%20Beams&cl_id=586&sid=533 ※ If you purchase one unit, we will ship it as is with the shipping label attached to the box. ※ A dedicated heater unit is required for cold regions below -20 degrees Celsius. If needed, we will include it free of charge, so please let us know.