0_4305 The study of 2D materials, and in particular the scattering with low-energy electrons, is of great interest in surface physics, as well as their several applications ranging from the development of electronic devices to novel detectors for particle physics. We report on the transmission of low-energy electrons through mono-layer graphene suspended on transmission electron microscopy (TEM) grid. Polycrystalline graphene was grown on copper via chemical vapor deposition (CVD) and transferred onto the TEM grid by a PMMA-assisted wet transfer at the CNI@NEST of Pisa. The sample has been then mapped by using micro-Raman spectroscopy in order to check the quality of graphene. A high-temperature annealing in vacuum have been performed in order to remove PMMA residues from the graphene. Scanning electron microscopy (SEM) allowed to estimate the graphene coverage and the TEM grid geometrical transmission. The custom-made monochromatic electron gun of the LASEC laboratory at Università Roma Tre has been employed to perform the transmission measurements. The electron beam has tuneable energy in the 30 -900 eV range with a resolution of 45 meV and a very good current stability. We measured the transmission of graphene suspended on the grid as a function of the electron energy with currents in the 200 pA range. The experimental apparatus allows to measure with a Faraday cup either the electron gun emitted current or the current transmitted through the graphene. Thus the transmission is obtained as the ratio of these two measured values. Furthermore, we performed spectroscopy with both X-ray photoemission (XPS) and electron energy loss (EELS) on the single-layer graphene and a tri-layer graphene for comparison. Through the first technique we measured the C1s signal to evaluate the graphene quality and, it has been found, that the main contribution to the line shape is sp² signal. The plasmon excitation has been measured through EELS. For the tri-layer graphene we observed the π-plasmon at 6.5 eV, while a second excitation appears at lower energy losses in the case of the mono-layer. All these spectroscopic results are the footprint of a good-quality suspended graphene.