40-Position AMP-Latch Header on 0.100" Grid
The 5499206-9: The four-wall shroud with a keying slot and mounting flange protects the pins during handling and guides the mating half into alignment; the long latch lock/eject hooks give a positive audible click when seated and let you lever the connector off the header without prying at the pins.
Gold Mating Surface and Solder Tail Finish
The mating contacts carry 30 µinch gold or gold-palladium over nickel — enough plating for repeated connect/disconnect cycles in a controlled environment without the contact resistance drift you get from tin-on-tin fretting. The solder posts are tin-plated (100 µinch) for good wetting in wave or hand-solder processes; the 0.110" post length gives enough stand-off for through-hole soldering without bottoming out against the board.