Binds with low affinity to muscular (alpha-1-beta-1-delta-epsilon/CHRNA1-CHRNB1-CHRND-CHRNE) and very low affinity to neuronal (alpha-7/CHRNA7) nicotinic acetylcholine receptor (nAChR). Expressed by the venom gland. Belongs to the snake three-finger toxin family. Ancestral subfamily. Orphan group II sub-subfamily.