K(+) channel that conducts outward rectifying tonic currents potentiated by purinergic signals (PubMed:24163367, PubMed:25148687, PubMed:30472253, PubMed:38409076). Homo- and heterodimerizes to form functional channels with distinct regulatory and gating properties (PubMed:25148687, PubMed:40011745, PubMed:40011746, PubMed:40307591, PubMed:40178898). Contributes most of K(+) currents at the plasma membrane of resting microglia (PubMed:38409076). Maintains a depolarized membrane potential required for proper ramified microglia morphology and phagocytosis, selectively mediating microglial pruning of presynaptic compartments at hippocampal excitatory synapses (PubMed:38409076). Upon local release of ATP caused by neuronal injury or infection, it is potentiated by P2RY12 and P2RX7 receptor signaling and contributes to ATP-triggered K(+) efflux underlying microglial NLRP3 inflammasome assembly and IL1B release (PubMed:38409076). {ECO:0000269|PubMed:24163367, ECO:0000269|PubMed:25148687, ECO:0000269|PubMed:30472253, ECO:0000269|PubMed:38409076, ECO:0000269|PubMed:40011745, ECO:0000269|PubMed:40011746, ECO:0000269|PubMed:40178898, ECO:0000269|PubMed:40307591}. This is the function of KCNK13 (potassium two pore domain channel subfamily K member 13, ENSG00000152315).