Grain-oriented electrical steel usually has a silicon level of 3% (Si:11Fe). It is processed in such a way that the optimal properties are developed in the rolling direction, due to a tight control (proposed by Norman P. Goss) of the crystal orientation relative to the sheet. The magnetic flux density is increased by 30% in the coil rolling direction, although its magnetic saturation is decreased by 5%. It is used for the cores of power and distribution transformers, cold-rolled grain-oriented steel is often abbreviated to CRGO. Standard size range of product Nominal Thickness (mm) Nominal Width(mm) Inner Diameter (mm) 0.23, 0.27, 0.30, 0.35 650-1200 508 Deviation of the Width, Thickness and length Nominal width Nominal thickness Thickness deviation Transversal Thickness deviation Width deviation Width tolearance Waviness % ≤650 800-1000 ≤1200 0.23, 0.27, 0.30, 0.35 0.23:±0.020 0.25:±0.025 0.30:±0.025 Other thickness ±0.030   ≤0.020 ≤0.025   ≤0.015   0--1   ≤1.5 Product Specification, Delivery weight and executive standard Product Specification Delivery Weight Executive Standard Thickness 0.23/0.27/0.39 * Coil Products delivery upon coil  coil weight ≤2-3 ton GB/T 2521.2-2016