  Plasma jets are ubiquitous in the Earth's magnetotail. Plasma jet fronts
(JFs) are the seat of particle acceleration and energy conversion. JFs are
commonly associated with dipolarization fronts (DFs) representing solitary
sharp and strong increases in the northward component of the magnetic field.
However, MHD and kinetic instabilities can develop at JFs and disturb the front
structure which questions on the occurrence of DFs at the JFs. We investigate
the structure of JFs using 5 years (2017-2021) of the Magnetospheric Multiscale
observations in the CPS in the Earth's magnetotail. We compiled a database of
2394 CPS jets. We find that about half (42\%) of the JFs are associated with
large amplitude changes in $B_z$. DFs constitute a quarter of these
large-amplitude events, while the rest are associated with more complicated
magnetic field structures. We conclude that the ``classical" picture of DFs at
the JFs is not the most common situation.
