The JST B12P-HL-A(LF)(SN) is a 12-position, dual-row board-to-cable header from the HL series, on a 0.156 inch (3.96 mm) pitch. The contacts are tin-plated brass, mated and post, which suits moderate mating-cycle duty in a fixed installation; the UL94 V-0 PA66 housing handles the thermal rise at full current. Operating temperature spans -25°C to 90°C, so it's comfortable in an industrial cabinet or outdoor telecom enclosure that stays above freezing.
How it compares within the HL series
The B04P-HL-A is the 4-position sibling at the same 3.96 mm pitch, same 7 A and 300 V rating, same dual-row layout, same latch holder. The only decision-relevant difference is position count — 12 circuits vs 4 circuits — so the choice is purely about how many circuits the BOM needs. No other spec changes, so the footprint and mating half stay consistent across the series.