Supply the Japanese original (strain) grades su ta Rousseau QX-200 radiation measuring device

Radioactive rays emitted from the element refers unstable nuclei spontaneously, (e.g., α-rays, β rays, γ rays, etc.) and stable elements forming stops radiation decay (decay products), a phenomenon known as radioactivity. The energy released during the decay called decay energy. Atomic number 83 (bismuth) or more elements are radioactive, but some elements of atomic number less than 83 (such as technetium) is also radioactive.