Selectrol® discs are designed to be a convenient source of viable micro-organisms which can be used as controls for a variety of QC and other testing purposes. To make Selectrol®, a first generation culture (a single subculture from the parent strain) is suspended in an inert medium and freeze dried in the form of discs. Selectrol® discs are convenient to store and versatile in their use. Fully traceable Guaranteed first generation derivatives from original NCTC®/NCPF® cultures Quality control micro-organisms of predictable biochemical reactions Manufactured under license from the UK Health Security Agency Culture Collections