The CAP CER 3900PF 630V C0G/NP0 1812 capacitor is a type of ceramic capacitor that offers a capacitance value of 3900 pF. It has a voltage rating of 630V and is classified as a C0G or NP0 capacitor, which means it exhibits minimal change in capacitance with respect to temperature. This capacitor is identified by the code "1812," which corresponds to a metric size of 4532.