Inhibits sodium channels Nav1.1/SCN1A (IC(50)=5.7 uM), Nav1.2/SCN2A (IC(50)=12 uM), Nav1.4/SCN4A (IC(50)=4 uM), Nav1.6/SCN8A (IC(50)=6.6 uM), Nav1.7/SCN9A (IC(50)=13.6-1030 nM), potassium channels Kv11.1/KCNH2 (IC(50)=4.7 uM), as well as high-voltage-gated calcium channels Cav1.2/CACNA1C (IC(50)= nM) (PubMed:19955179, PubMed:30661758, PubMed:31234412). Also blocks mechanosensitive ion channels (also named stretch-activated channels or SACs) and the hypotonic cell swelling induced calcium increase associated with the activation of such channels (Ref.3). It can thus be useful in treating cardiac ventricular disturbances (Ref.3). Also induces analgesia in mammals (Ref.2). Expressed by the venom gland. The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin. This toxin does not have effect on sodium channels Nav1.3/SCN3A (IC(50)=24 uM) and Nav1.5/SCN5A (IC(50)>40 uM), and potassium channels Kv1.1/KCNA1, Kv1.4/KCNA4, Kv11.2/KCNH6 and Kv11.3/KCNH7 (IC(50)>200 uM). Belongs to the neurotoxin 30 (phrixotoxin) family.