Wonder wire is composed of a extremely small diameter tungsten metal core with elemental boron deposited on the tungsten's surface. This boron filament is available in aerospace purity grades from Specialty Materials located in Lowell, Massachusetts, USA. They have two sizes. .004 and .0056 inch diameter. The big obstacle in obtaining this material from Specialty Materials is that they have a one pound minimum order. The .004 is $1355 per pound. The .0056 is $1602. There are many thousands of feet per pound so the price per foot is cheap. Note that is one thousand three hundred fifty five dollars per pound not $13.55