Board-to-Board Mezzanine Fit: Pitch and Stack Height
The 71991-304LF: The mated stack height is 11.04mm — that dimension sets the board-to-board spacing in a mezzanine stack, so the header height plus the receptacle body must sum to that number.
The gold-on-gold mating interface avoids the tin-whisker risk that can arise with tin-on-tin contacts in high-vibration environments.
Housing Material and Flammability Rating
The insulator is a glass-filled thermoplastic rated UL94 V-0. That flame rating is required for connectors inside enclosed equipment — telecom switches, industrial controllers, and automotive ECUs all specify V-0 for the plastic components in the current path.
The base product number is 71991; the -304LF suffix encodes the 8-position, dual-row, gold-plated variant. The same base covers other position counts and plating options in the Dubox™ family.