What This Housing Is and What It Needs
The 87977-8: It is a free-hanging (in-line) crimp housing — meaning it terminates individual wires that are crimped into separate female socket contacts, then inserted into the rear of the housing. The housing itself is a black thermoplastic shell rated for -65°C to 105°C, which puts it in the industrial and automotive operating envelope, not just benign indoor use. The key thing to know upfront: contacts are not included. This is an empty shell, and you order the crimp sockets separately to match your wire gauge.
20 Circuits, Dual-Row, 2.54mm Pitch — The Fit Check
The 20 positions are arranged in two rows spaced 0.100" (2.54mm) apart, matching the same pitch as the row spacing. That gives you a compact 10-per-row layout that mates with the corresponding AMPMODU Mod IV 20-position dual-row header (also 0.100" pitch). The dual-row arrangement means the housing is wider than a single-row equivalent — roughly 0.500" across the body — so confirm your wire bundle and connector clearance before committing the harness layout.
Crimp Termination and Contact Selection
Termination is crimp, not IDC or solder. You select the appropriate AMPMODU Mod IV female socket contact for your wire gauge (typically 22-28 AWG for this series), crimp it onto the stripped wire, and insert it into the housing cavity until the retention lance locks. The housing has no integral latch — retention relies entirely on the contact's own locking tang engaging the housing cavity wall. The wide -65°C to 105°C range means the thermoplastic housing maintains its dimensional stability and contact retention across thermal cycling in an engine bay or industrial cabinet.