Voltage-gated channel mediating the exchange of chloride ions against protons. Functions as antiporter and contributes to the acidification of the late endosome lumen. The CLC channel family contains both chloride channels and proton-coupled anion transporters that exchange chloride or another anion for protons. The presence of conserved gating glutamate residues is typical for family members that function as antiporters. 2 chloride(in) + H(+)(out) = 2 chloride(out) + H(+)(in) Testis, ovary, small intestine, brain and skeletal muscle. Low level expression in aortic and coronary vascular smooth muscle cells, and aortic endothelial cells. Isoform 3 is only detected in kidney. N-glycosylated on several asparagine residues. The disease is caused by variants affecting the gene represented in this entry. Belongs to the chloride channel (TC 2.A.49) family. ClC-6/CLCN6 subfamily.