Right-Angle Header with Mounting Flange
The 87427-1203 is a 4.2mm pitch right-angle pin header from Molex, described as a 4.2MM WTB RAHDR HT /OMNTFLG. The mounting flange provides mechanical retention to the board, which is useful when the mated cable assembly will experience strain or vibration — the flange takes the shear load off the solder joints.
No stock-holding claim; sourced per inquiry.