feature:1. When the siren detects smoke, the siren will sound and the LED light will flash.2. Built-in high-decibel tweeter, the sound is clear and loud. The 3M distance is greater than or equal to 95 decibels.3. The shell of the smoke detector is made of high-quality ABS material, which is environmentally friendly, sturdy and durable.4. Built-in battery, don't worry about power failure. The wireless outdoor distance is 100m.5. Suitable for families, factories, etc.describe:The alarm speed is fast, the sound is bright, the response is sensitive, and the performance is stable.Specification:Working voltage: DC 9VStandby current: 10uaAlarm current: 80mAAlarm mode: sound and light alarm (independent)Working temperature: -10C~+50CWorking humidity: 95%RHAlarm sound pressure: 85dbKong control area: 20 square metersAppearance size: 12*12.5*5.5cmPower supply: battery (not included)Package Included:1*smoke detectornotes:1. Due to manual measurement, please allow an error of 0-1 inch. thank you for understanding.2. The monitor is not calibrated, and the color of the object shown in the photo may be slightly different from the actual product.