Avoid conventional color bulbs to monitor a phase/line signal, and replace them with these new powerful LED Signal Indicators with Built-in buzzers with various advantages over the old bulbs.  This New pilot lamp uses LEDs as a light source which is energy-saving & Built-in Buzzer, small and compact, and highly durable which adds a systematic and classy look to your control dashboard or signal monitoring spot on any device or chassis. The cover of this pilot indicator is made of PC plastic to provide good shock resistance and can be used as an indication for pilot lights, accident signals, or other power availability check signals in the circuits of telecommunication and electrical apparatus.