The 821KD07J Varistor with Through Hole RoHS manufactured by Yageo is an electronic component with a maximum AC current of 1.2A. It is designed for transient voltage suppression and is constructed with two zinc oxide varistor chips and four leads encapsulated in a UL 94V-0 flame retardant epoxy resin. The part has a rated voltage of 400V and a leakage current of < 2.6mA, making it suitable for protecting sensitive logic and other circuits from voltage spikes. It also has a low clamping voltage and a wide operating temperature range of -30°C to +85°C, making it an ideal choice for applications requiring robust protection against surges.