What this unshrouded breakaway header does in a board stack
The 77315-101-25LF: Rated 3 A per contact, the current is limited by the tin-plated solder tails and the single-row contact density — derate above 25 °C per the standard curve. The -65 to 125 °C operating range suits environments from cold storage to under-hood electronics.
Mating interface and plating — what the gold means for cycle life
The post finish is tin (78.7 µ in / 2.00 µm), which solders cleanly but does not carry the same cycle rating.