What this housing is — and what it is not
The Molex 0050579420 is a 20-circuit, single-row receptacle housing from the SL 70066 series. The black polyester housing is glass-filled for dimensional stability under reflow and vibration.
The one line that saves a BOM re-spin
Contacts are not included. That note is the most common trip point on this part — a buyer orders twenty housings but forgets the 20 female socket crimp terminals.
Mating half and fit check
This receptacle mates with the SL 70066 series pin header — a 20-position, single-row, 0.100" pitch header with a matching latch ramp. The latch lock engages the header's locking ramp for a vibration-resistant mate. No contacts, no header — the housing alone is an incomplete interconnect.