The number of theoretical plates correlates with the particle size. The smaller the particle, the higher the number of theoretical plates can be. A typical number of plates for 5 µm particle size is about 80.000 N/m, for 3 µm 130.000 N/m. Columns with high plate numbers are considered to be more efficient than columns with lower plate numbers. A column with a high number of plates will have a narrower peak at a given retention time than a column with a lower number of plates.