The automatic fire detectors of the AVENAR detector 4000 series feature a superb accuracy and swiftness in detection. The range includes versions with rotaries, manually and automatically addressable, and versions without rotaries for automatic address setting. Multi-criteria detectors can support, if single sensors are not sufficient. They have highest stability against deceptive phenomena and response to a broad range of fires. The versions with two optical sensors (dual‑optical) detect the lightest smoke. The versions with heat sensor detect fires with rapid temperature increase or with a maximum temperature value. CO fire detectors react promptly to smoldering and suit better for applications with dust, steam, cooking vapors. Included CO-detection helps to support an even more reliable fire detection and leads in parallel to a higher false alarm stability.