N-Methyl-N-(pentacosa-10,12-diyn)-propargylamine organizes itself into an unusual supramolecular pH- and thermo-responsive system. Studies have showed that submillimetric length hollow laths form this unique structure in the presence of hydrochloric acid. Specific chemical modifications on the initial molecule and small-angle neutron scattering experiments were performed to understand the structure of this system. Our results allow us to suggest a possible structure of the laths.