AM4-64 is a fixable, activity-dependent fluorescent nerve terminal probe. AM4-64 functions similarly similarly as SynaptoRed™ C2 (equivalent to FM®4-64), but with the additional property of being fixable. Thus, AM4-64 is a useful tool for synapse studies where subsequent fluorescent immunochemistry is desired. AM4-64 and FM®4-64 have identical excitation and emission wavelengths.    FM is a registered trademark of Thermo Fisher Scientific.