So far, SAR measurements are performed using an electric field probe, immerged within a phantom filled with a liquid reproducing the electrical properties of head or body tissues. As the SAR is defined within a given volume (1gr or 10gr), a scanning operation is required for integrating the measured E-field components over a distributed area, thus involving mechanical displacements of the probe in the phantom using a robot. Various SAR testbenches are available on the market [1] [2]. Nevertheless, such SAR measurement technique with a robot is quite long and costly and do not allow a systematic and real time SAR evaluation. Recent works have presented fast-SAR evaluation techniques, considering appropriate SAR apparatus without movement, combined with algorithmic procedures for accelerating and recovering complete SAR distribution [3][4][5][6]. The number of required probes remains quite large for reducing the uncertainty, thus dedicating such ultra fast SAR apparatus to production line testing. In this article, we investigate on the replacement of the robot by miniature probes array placed inside the phantom (see figure 1), then allowing an instantaneous spatial/volume discrete E-field scan without displacement. We study the influence of the sensors depending on their dimensions and we analyze the SAR uncertainty.