In recent years, Reconfigurable intelligent surfaces (RISs) have gotten increasing attention for their potential in wireless communication systems. With the development of the RIS-based system, the modulation rate has become an important issue. In this paper, a 1-bit dual linearly polarized RIS element for high-speed modulation is proposed. For each polarization, a pair of PIN diodes is responsible for independent control of the corresponding reflection coefficient, which, namely, can exhibit a 180-degree reflection phase difference by switching the 0/1 state of RIS. Preliminary experiments show that at high modulation rates, the proposed element promises more stable performance compared to some existing designs, which is of great significance for the application of RIS in various scenarios such as wireless communication and radar detection.