Industrial applications have been widely revolutioned by additive manufacturing processes. It allows the ad-hoc production of low-volume customize objects such as tools, medical protheses, devices or even tissues. At any case, a robust knowledge of mechanical and the bulk acoustic properties of these commonly used materials are needed. A meticulous ultrasonic Non-Destructive Testing technique is applied with the aim of characterize 3D-printed photopolymers materials. Algebraically, measured longitudinal and transversal wave velocities are converted into Young's and Shear modulus. Results show that the set of analyzed materials are suitable to cover a wide range of applications since its mechanical values ranges from 4 to 16 GPa. No significant differences between the three orthogonal axis have been found.