Inhibits voltage-gated potassium channel rKv1.1/KCNA1 at nanomolar ranges (IC(50)=90 +-2 nM, reduction of current by 30% at 50 nM or toxin). 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 03 subfamily.