What it is and where it fits
The JST B4P-VH(LF)(SN) is the 4-circuit member of the VH series — a single-row, single-wall shrouded header rated 10 A per circuit at 250 V. The locking ramp on the shroud mates with the matching VH plug housing to give positive retention without a secondary latch, which matters in any harness assembly where vibration or cable pull could unseat the connection over time. The 0.156 inch (3.96 mm) pitch and square male pin geometry are sized for the matching VH crimp housing and its corresponding terminal. The 0.370 inch (9.40 mm) insulation height and 0.303 inch (7.70 mm) mating contact length define the engagement envelope with the housing. Tin plating on both the mating interface and the solder post is the right choice for high-cycle or field-serviceable interconnects where gold would be overkill, though it carries a lower mate/unmate cycle ceiling than gold-plated alternatives in the same pitch class. The brass contact body and PA66 nylon housing deliver the UL94 V-0 flammability rating the part carries.
How it compares to the right-angle sibling
The B4PS-VH carries the same 4-position count, 3.96 mm pitch, 10 A, and 250 V ratings — the difference is mounting orientation. B4PS-VH is right-angle through-hole; B4P-VH(LF)(SN) is vertical through-hole. In a panel or DIN-rail wiring block layout the vertical mount takes the board edge perpendicular to the panel surface, while the right-angle variant routes the cable exit parallel to the panel face. The mated stack height for both is 16.5 mm, so the z-height envelope is identical — the choice is driven by routing direction, not by electrical or mechanical rating.