  We have realized encapsulated trilayer MoS$_2$ devices with gated graphene
contacts. In the bulk, we observe an electron mobility as high as
7000~cm$^{2}$/(V s) at a density of 3 $\times$ 10$^{12}$~cm$^{-2}$ at a
temperature of 1.9~K. Shubnikov--de Haas oscillations start at magnetic fields
as low as 0.9~T. The observed 3-fold Landau level degeneracy can be understood
based on the valley Zeeman effect. Negatively biased split gate electrodes
allow us to form a channel that can be completely pinched off for sufficiently
large gate voltages. The measured conductance displays plateau-like features.
