3M 5100 Series 2.54 x 2.54mm Right Angle PCB Mount Polarized Connectors feature center polarization.
These female connectors 5100 Series 2.54mm Pitch PCBs mate for mounting with low profile enclosed connectors and are used in board stacking applications such as a motherboard/daughter board and allow two PCBs to be mounted in tandem using a 90mm female connector. ° and another 90° connector
The main features are: