A ceramic capacitor with the designation CAP CER 12PF 100V C0G/NP0 and part number 1812 has a capacitance of 12 pF with a tolerance of ±10% and operates at a voltage of 100V. It is classified as a C0G or NP0 type capacitor, which are known for their stable characteristics over temperature. The metric equivalent to the part number 1812 is 4532.