This recombinant toxin inhibits the mammalian voltage-gated potassium channels Kv1.3/KCNA3 (IC(50)=28 nM). Kv1.1/KCNA1 and Kv1.2/KCNA2 potassium channels are also weakly inhibited (IC(50)=1.73 uM and IC(50)=12.63 uM, respectively). Expressed by the venom gland. Has the structural arrangement of an alpha-helix connected to antiparallel beta-sheets by disulfide bonds (CS-alpha/beta). Belongs to the short scorpion toxin superfamily. Potassium channel inhibitor family. Alpha-KTx 12 subfamily.