Blocks mammalian Kv4.2/KCND2 and Kv4.3/KCND3 (By similarity). Blocks mechanosensitive ion channels in rat astrocytes, without having effect on whole-cell voltage-sensitive currents (By similarity). Expressed by the venom gland. The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin. The primary structure of this mature peptide is identical to that of kappa-theraphotoxin-Ps1b (Phrixotoxin-2) from Paraphysa scrofa (AC P61231). Belongs to the neurotoxin 30 (phrixotoxin) family.