Toroidal Transformers offer smaller size, lower audible noise, approximately 1/10th of the stray magnetic field, and greater efficiency than conventional laminated isolation transformers. The primary reason that toroids offer these advantages is the efficiency of the core. For lower frequency, audio and power designs, the core is wound from a continuous strip of ferro-magnetic material such as silicon steel and/or nickel. The core manufacturing process ensures that all of the grain in the material are aligned in the magnetic direction. In the conventional laminated design about 40 % of the grain is perpendicular. Unlike the laminated design, there is no air gap in the toroid core, yielding a higher stacking factor. By spacing the windings evenly around the entire toroid core, it is possible to design and operate at flux densities approximately 30 % higher than a laminated design, as well as reduce the stray magnetic field. Toroids are also available in molypermalloy, ferrite, powdered iron and various materials, all offering the same high efficiency advantages of the core.