6.35 mm pitch, 12 positions — one cavity is intentionally empty
The 1586681-2: This Universal MATE-N-LOK header from TE Connectivity AMP Connectors carries 12 total positions but only 11 are loaded with male pins — the empty cavity serves as a keying feature to prevent mis-mating with the wrong receptacle. The 0.250" (6.35 mm) pitch is generous, giving you room for higher-current contacts or thicker insulation without crowding the board.
Locking ramp and through-hole mounting
Through-hole mounting with solder termination gives you a mechanically robust joint that survives repeated mating cycles. The insulation height of 0.550" (13.97 mm) and post length of 0.155" (3.94 mm) set the board-to-mating interface height; check your enclosure clearance if you're stacking boards.