keep your house or office security

many offices and houses have installed the smoke alarm and gas alarm. but since there's any danger from it, so they think the equipment will always work and inform them the danger like before.

it's a wrong thinking and stupid imaging. as the products' introduction said, we shuld check the smoke alarm, gas alarm every month. whether the battery was ended, whether the dust fulled the ventilation slots, or whether the nails were loosend.

we bought them with a wish for informing us the danger, but not to keep us safe. we should always keep a scan manner on the circumstance around us.

Best regards