Nested around the blade energy channel, the emitter control is a sophisticated matrix which is essential to lightsaber construction. A balanced ring of cycling field energizers emits a magnetic containment field that isolates the plasma flow, giving the blade its shape and preventing the lightsaber from incinerating itself. A superconductor uses polarity to draw the plasma arc back to the lightsaber, converting the returning stream into energy that recharges the power supply. Thus power loss is only experienced when plasma is spent cutting through solid matter. Most emitter controls have a uniform appearance and must be clearly marked to indicate which end is which. Accidentally inverting the component while performing routine maintenance on a lightsaber will reverse the field polarities, causing a deadly explosion when the lightsaber is ignited. Despite the sheer complexity of the matrix, Force devotees have produced a number of emitter controls since the advent of the technology some 5,000 years ago and these rare devices are highly prized by collectors.