The CAP CER 390PF 1KV X7R 2220 is a type of ceramic capacitor. It has a capacitance value of 390 picofarads and tolerates up to ±5% variation in its value. Additionally, it can withstand a maximum working voltage of 1000 volts (1 kilovolt). This component belongs to the X7R group of ceramic capacitors, which is commonly used for various electronic applications.