Light pulse atom interferometers are implemented for precision measurements in various areas such as gravito-inertial measurements or measuring fundamental constants. In addi- tion, atom interferometers with an increased sensitivity are potential candidates for testing fundamental physics in gravitation, dark sector physics, or for gravitational waves detection. In order to increase their sensitivity, a promising idea is to increase the momentum sepa- ration between the two arms of the interferometer. We are at present constructing such a Large Momentum Transfer (LMT) atom interferometer. Bragg diffraction is a corner stone for new schemes in the LMT beam splitters. In this “poster” session, I will present a 80 h ̄k LMT-interferometer based on sequential high order Bragg pulses. I will also comment the inherent multi-state nature of quasi-Bragg interferometers, leading to spurious interferome- ters and complicate the phase estimation. Finally, I will present experimental study of the phase response function of our interferometer.