The Alpha BI range has a special coated finish that eliminates the need for casing, providing closer proximity between the coil surface and the magnetic field. This range offers different depths/sizes of magnetic fields.

Smaller coils deliver more focal and shallow magnetic fields, whilst larger coils produce comparatively broader and deeper magnetic fields. The branding iron (BI) design of these coils allows for easy current reversal via coil rotation and is practical during adjacent placement of two coils.

These coils are compatible with all Magstim research stimulators.