Abstarct: The "SST" connection is the first prequalified partially restrained connection. In this study, numerical evaluation of the behavior of this connection with commonly used profiles in Iran with some comparisons in Abacus software has been investigated. In this study, five specimens In accordance with AISC 358 to investigate the acceptability of SST connection with commonly used profiles in Iran. The results of the present study show that all five specimens made in accordance with the requirements of AISC 358 have been able to satisfy the general requirements of prequalified. In addition, the five specimens were able to show good seismic behavior, so that up to 0.06 radians, none of the specimens had any decrease in resistance and their moment-rotation curve has always been increasing. Maximum pre-tensioning in the five specimens yield-lixnk flange bolts increased the stiffness connection by 11% to 12%, but was less than 1% more effective in improving the moment resistance behavior of the connection. Also, the maximum pre-tensioning of the yield-lixnk flange bolts and the strengthening of panel zone the doubler plate for the five plate specimens resulted in an 11% to 14% increase in stiffness compared to with doubler plate specimens, while its effect on the moment the capacity connection was less than 1%. All fifteen SST connections in this study are classified as a partially restrained and full-strength connection. A comparison of the three samples with SST, SST_R and RBS connections showed that the RBS connection decreased with 0.06 radians of rotation. Whereas, the other two connections have not experienced any resistance reduction. Also, the RBS connection stiffness is greater than the two. The panel zone at the RBS connection enters the plastic interval, while the other two samples always exhibit elastic behavior. The hardness stiffness of the panel zone is equal to the SST_R and RBS connection, and the hardness stiffness of the SST connection is lightly higher than the two samples. In another comparison between the two SST and RBS_R connections, the results showed that the RBS_R connection hardness was higher than the SST connection, and its resistance was slightly higher. The panel zone behavior is elastic in both models and the stiffness of the SST connection is slightly higher. Examples of graphical results and equivalent plastic strain diagrams show that yields on the SST connection occur only in the reduced section. SST_R, RBS, and RBS_R connections are categorized in the partially re-strained connections and full-strength connections.