4-Pin Vertical Unshrouded Header — 3.50 mm Pitch
The 1986718-4: The 3.50 mm pitch (0.138") is wider than the common 2.54 mm grid — the footprint won't fit a 0.100-inch pattern without adjustment. Tin is good for moderate mating cycles (50-100 mates typical) in clean indoor environments — not for high-vibration or corrosive atmospheres where gold would be specified.
No official successor or pin-compatible cross-reference is listed. The base number 1986718 covers the series; variants differ by position count and plating. For a direct replacement, stick with the same base number and verify the position count and tail length.
Unshrouded design means no plastic shroud around the pins — the mating receptacle must align visually or use its own keying. This saves board space but offers no polarisation against mis-mating.