Conductivity (dc and ac), ESR-properties and proton relaxation rates of the charge transfer complex Tetrathiafulvalene N,N′-dicyanonaphthoquinonediimine in the temperature range be tween 300 K and 3.8 K are reported. This salt belongs to the unusual group of organic conductors, in which segregated donor and acceptor stacks are associated in a pairwise manner. The physical properties, which are compared with TTF-TCNQ, give evidence of non-stoichiometric charge transfer (ρ ≠ 1). A metal like state can be identified for T> 70 K, as is seen from the weak temper ature dependence of the conductivity (σrt ≈ 30 Scm-1) and the susceptibility (Xrt ≈ 7.5 ⋅ 10-4 emu/ mole) and from the Korringa like temperature dependence of the proton relaxation rates. The drop of the susceptibility at Tc ≈ 70 K and the activated temperature dependence of the conductivity for T < 70 K are explained by a metal-to-semiconductor transition.