The device was different than the patented klystron, or even earlier magnetron designs. The cavity magnetron uses physical cavities and a magnetic field to create microwave energy.

The magnetron may have insulators made of beryllium oxide and inhaling dust from the insulator even one time can cause an incurable lung condition. Luckily, you can’t get a lung problem from ...

Bernard Lovell, The Cavity Magnetron in World War II: Was the Secrecy Justified?, Notes and Records of the Royal Society of London, Vol. 58, No. 3 (Sep., 2004), pp. 283-294 ...

High Power Impulse Magnetron Sputtering (HiPIMS): A sputtering technique employing high power pulses at low duty cycles to generate a highly ionised plasma, resulting in dense and high-quality ...