Blocks voltage-gated potassium channels Kv1.1/KCNA1 (IC(50)=0.6 nM), Kv1.2/KCNA2 (IC(50)=5.4 nM), Kv1.3/KCNA3 (IC(50)=0.014 nM) potently, and moderately block intermediate conductance calcium-activated potassium channels KCa3.1/KCNN4 (IC(50)=225 nM) (PubMed:15588251, Ref.1, PubMed:16234482). Also shows activity on muscle-type nicotinic acetylcholine receptor (nAChR), since it reversibly and dose-dependently inhibits acetylcholine-induced current through mouse muscle-type nAChR heterologously expressed in Xenopus oocytes (IC(50)=1.6 uM) (PubMed:31276191). Expressed by the venom gland. Has the structural arrangement of an alpha-helix connected to a beta-sheet by disulfide bonds (CSalpha/beta). LD(50) is 2 ug/kg by intracerebroventricular injection into mice. Does not show activity on Kv1.4/KCNA4, Kv1.5/KCNA5, Kv1.6/KCNA6, Kv1.7/KCNA7, Kv3.1/KCNC1, Kv11.x/KCNH, KCa1.1/KCNMA1, KCa2.1/KCNN1, KCa2.2/KCNN2, and KCa2.3/KCNN3 (PubMed:15588251). Does not show activity on Kv3.2/KCNC2 (PubMed:16234482). May not inhibit neuronal human alpha-7 nAChR, since it does not inhibit alpha-7 alpha-bungarotoxin binding (IC(50)~20 uM) (PubMed:31276191). Belongs to the short scorpion toxin superfamily. Potassium channel inhibitor family. Alpha-KTx 03 subfamily.