Pitch and footprint — why 2.50mm matters for your board
The 1971921-3: The single-row 3-position layout, with 2 positions loaded, means the board footprint has three through-holes but only two carry a contact; the empty position is a placeholder for future expansion or a keying slot.
Shrouded and locked — vibration-proof mate
For a harness routed near a motor or in a portable appliance, this latch prevents intermittent contact from cable tug.
Glow wire compliance — appliance safety gate
Glow wire compliant means the housing material passes the glow-wire test — a requirement for household appliances, lighting, and HVAC controls.
Thermal range and plating — field-service reality
Operating from -40°C to 120°C covers automotive under-hood and industrial cabinet environments. Tin-on-tin interfaces are reliable when the connector is mated and left alone; repeated wipe can wear the plating and increase contact resistance.