Function: 1. AD1622FSV model, flame retardant, high durability, and environmental protection. Its solid construction is ideal for long-term work. 2. Round shape design, clear printing, and high brightness make it easy to identify the working status. It has a long lifespan and low energy consumption. 3. The sealed shell effectively reduces dust ingress into the indicator light, extending its lifespan for more durable use. 4. Suitable for electrical, telecommunications, machine tools, ships, printing, and other equipment for signal indication and voltage display. 5. 60~500V AC digital voltage signal indicator, 20~75Hz frequency range, safe and convenient to use. Specification: Item Type: Voltage Signal Indicator Material: Plastic Model: FSV AD16-22 Voltage Range: 60~500V AC Frequency Range: 20~75Hz. Package List: 1 x Voltage Signal Indicator Note: Be careful not to exceed the voltage range during installation.