6.35 mm pitch and gold contacts define the board fit
The 350834-4: This is a 6-position, 3-row header from TE's Universal MATE-N-LOK series, with a 0.250" (6.35 mm) pitch that sets the board footprint and the per-contact current ceiling. The locking ramp gives you a positive mechanical latch against the mating receptacle, so the pair stays mated under vibration without relying on the contact friction alone.
The 3-row arrangement with 0.250" row spacing keeps the routing lanes open between rows.
The 1-2823056-2 is a different connector family — it's a 12-position, 2-row, 0.100" pitch receptacle with tin-plated contacts, forked contact shape, and a black glass-filled PA46 housing. It is not a functional second-source for the 350834-4: different pitch, position count, row count, contact finish, and contact geometry. If you need a 6-position, 0.250"-pitch header with gold contacts, the 350834-4 is the correct part.