The S3 is a cell-sorting system for core facilities and individual research labs. It is designed to ease bottlenecks by serving as a supplementary instrument for basic cell-sorting work. Equipped with one or two lasers (488 nm and either 561 or 640 nm), the S3 enables up to four-color detection along with forward- and side-scatter detectors. It is suitable for sorting cells expressing fluorescent proteins and cells labeled with fluorescent markers, and for isolating individual cells for single-cell PCR or digital PCR studies. Key attributes of the system include simplified experimental setup, automatic cleaning, and small benchtop footprint.