Highly potent toxin against both insect and some mammalian sodium channels (Nav). It potently inhibits inactivation of insect sodium channels of B.germanica (BgNav1) (EC(50)=7.8 nM) and also delays the inactivation of mammalian Nav with potent activity on Nav1.3/SCN3A and Nav1.4/SCN4A (hNav1.1/SCN1A; EC(50)=102.1 nM, rNav1.2/SCN2A; EC(50)=156.1 nM, rNav1.3/SCN3A; EC(50)=9.4 nM, rNav1.4/SCN4A; EC(50)=15.4 nM, hNav1.5/SCN5A; EC(50)=132.7 nM, mNav1.6/SCN8A; EC(50)=66.9 nM, hNav1.9/SCN9A; EC(50)=73 nM). 1 uM is enough to completely inhibits the inactivation, resulting in sustained non-inactivating currents. In addition, the toxin significantly enhances the recovery from inactivation, and the open state is not required for the toxin to interact with the channel. In vivo, injection into brine shrimp (Artemia salina) stops movement or causes death after 24 hours (EC(50)=0.4 uM)