The Z-TER (Z 21500) is a French model of electric multiple unit regional passenger train, manufactured by Alstom and Bombardier Transportation, and operated by SNCF.

They are derived from the French diesel passenger regional train "X-TER" (X 72500), and is the first regional train to reach 200 km/h.

Their main characteristic is their ability to travel at 124.27 mph, which constitutes a first for TER self-propelled equipment.

This ability, used every day over several sections of conventional lines, is also operated for the first time on a high speed line since 2017.

This is a first in France, thanks to a adaptation of eight of these elements to signaling specific to LGVs, then renumbered as Z 21700.