Features Good Protection: Able to prevent damage to electrical appliances caused by frequent switching and unstable voltage. EASY ADJUSTMENT - Supports manual adjustment of over-voltage, under-voltage, over-current protection values, and is very simple to use. 【Best Display】Equipped with surge protection, undervoltage protection and voltage display and measurement for electrical safety. Other functions: Reset mode selection, fault query and factory recovery functions, and the surge and undervoltage protector is reliable. Convenient Installation: Lightweight, small volume, the installation of this surge and undervoltage protection device can be completed quickly. Specification: Item Type: Surge Protection Material: flame retardant PC Current: 1-40A uvo surge protection value range: 240V-300V Undervoltage protection value range: 140V-210V Shutdown time: 2s, 1-300s adjustable Automatic recovery protection time: 30s, 1-300s adjustable Nominal frequency: 50/60H Error: 2% Voltage measurement accuracy: 1% Nominal insulation voltage: 400V Output contact: 1No Electrical life: 100000 times Mechanical life 1,000,000 times Degree of protection: IP20. Elevation: ≤ 2000 m Operating temperature: -50°C to 55°C. Humidity: ≤ 50% at 40°C, non-condensing Humidity temperature: -30°C - 70°C Package list: 1 x surge protection Package List 1 x Over Under Voltage Protector