Mediates electroneutral potassium-chloride cotransport when activated by cell swelling. May contribute to cell volume homeostasis in single cells. May be involved in the regulation of basolateral Cl(-) exit in NaCl absorbing epithelia. Inhibited by WNK3. Homomultimer and heteromultimer with other K-Cl cotransporters. Detected in embryo, adult heart, erythrocytes, brain, kidney, stomach, ovary, testis and liver. Expression levels remained constant upon induction of erythroid differentiation of embryonic stem cells. Not detected in reticulocytes, but present during differentiation of erythroleukemia cells to erythroblasts. N-glycosylated. Activated by N-ethylmaleimide (NEM). Inhibited by DIOA. Belongs to the SLC12A transporter family.