Expressed by the venom duct. The cysteine framework is III (CC-C-C-CC). Classified in the M-1 branch, since 1 residue stands between the fourth and the fifth cysteine residues. The mature sequence of Reg3.4 described in Franco et al., 2017 corresponds to the mature sequence of conotoxin reg3l (AC P0DQO8). Belongs to the conotoxin M superfamily.