Note: The product does not include app features, nor does it support base station connection. Comprehensive Protection: This kit has one heat alarm and two smoke alarms, providing full coverage and home protection; not triggered by smoke, dust, or cooking vapor, an ideal heat alarm for kitchen Highly Accurate Detection: The interlinked smoke alarm use a photoelectric sensor for fast and accurate smoke detection; it detects a sudden rise in temperature, from 129°F (54°C) to 149°F (65°C), due to its sensitive NTC thermistor Wireless Interconnection: These are Link+ series alarms and can be interlinked to form a wireless network; all devices will go off when one is triggered, giving an early warning to everyone in your home 10-Year Battery Life: Equipped with sealed 10-year lithium batteries, so there’s no need to replace the battery frequently; your home is protected 24/7, even when the power goes out Durability & Easy Installation: Made of corrosion-resistant, flame-retardant material, they have long-term reliability and durability; easy to install on any wall or ceiling in minutes using the accessories included Ready to Use: 1 × XH02-W Heat Alarm, 2 × SD19-W Smoke Alarms, 3 × Mounting Bracket, 6 × Screws, 6 × Anchor Plugs, 3 × CR123A Batteries , 1 × User Manual included; simply press the test/silence button to interconnect your wireless smoke detectors (the alarms in one multi-pack have already been interconnected) and then start to protect your home