Unshrouded Push-Pull Mating Interface
The 9-146256-0-04: That means the mating receptacle slides directly onto the square pins without a keying shroud, so orientation and alignment depend on the board layout and the mating half's housing. Common mates include AMPMODU Mod II receptacles and IDC sockets with the same 0.100" pitch. That tail length fits standard 1.6mm PCBs with enough protrusion for a reliable solder fillet.
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