Lectin-like receptor for natural killer (NK) cells. Heterodimer formation with KLRE1 mediates inhibition of NK cell cytolytic activity. Heterodimer with KLRE1. Interacts with PTPN6. Expressed in natural killer (NK) cells. Contains 2 copies of a cytoplasmic motif that is referred to as the immunoreceptor tyrosine-based inhibitor motif (ITIM). The phosphorylated ITIM motif can bind the SH2 domain of several SH2-containing phosphatases leading to down-regulation of cell activation.