Renal sodium, potassium and chloride ion cotransporter that mediates the transepithelial NaCl reabsorption in the thick ascending limb and plays an essential role in the urinary concentration and volume regulation. Electrically silent transporter system. Activated by WNK3. When phosphorylated, interacts with PPP3CB. Predominant in kidney. The 3 isoforms are differentially distributed within the kidney: B almost exclusively in cortex, F almost exclusively in medulla, and A about equally distributed. Belongs to the SLC12A transporter family.