A new class of metal-insulator tunneling transistor (MITT) devices is proposed and investigated. The planar dual-gate structure allows for complete gate field penetration of the transistor channel to modulate tunneling current across the channel. For a 5-nm channel length, with contact geometries that reflect the reality of fabricating at such a scale, we show that a 10% decrease in the effective electron tunneling length results in a <inline-formula> <tex-math notation="LaTeX">5.5\times </tex-math></inline-formula> increase in current up to <inline-formula> <tex-math notation="LaTeX">4.4{\times }10^{-6} mA/\mu {}m </tex-math></inline-formula>. The device demonstrates an ON-/ OFF-current ratio that is <inline-formula> <tex-math notation="LaTeX">2.5\times </tex-math></inline-formula> greater than that of a complementary metal-oxide-semiconductor (CMOS)-style MITT with a 5-nm channel length. Without the use of a second gate insulator, the source-to-drain current density is more than 10 4 times greater than the source-to-gate leakage current density, indicating the efficacy of the presented realistic MITT implementation.