The overall physical form of the applicator that delivers the field, such as a disc, a loop or ring, or a flat mat. Accessory shape sets how the field is laid out over the target area: a disc concentrates it in a small spot, a loop surrounds a limb, and a mat spreads it across a wide surface. The shape also determines how the field is measured and which coverage figures appear in the report.
A PEMF accessory takes a few physical forms, and the form sets how the field is laid out. A disc concentrates the field in a spot, a paddle puts that disc on a handle, a loop is a ring that surrounds a limb, and a mat spreads many coils across a wide surface. A loop is described by two diameters: the inner diameter of its open center and the outer diameter of the whole ring.
