Cation-chloride cotransporter which mediates the electroneutral transport of chloride, potassium and/or sodium ions across the membrane. Plays a vital role in the regulation of ionic balance and cell volume. Inhibited by bumetanide. Homodimer. Strongly expressed in rectal gland, brain, gill and intestine. Also detected at lower levels in heart, kidney, and testis. Belongs to the SLC12A transporter family.