What this connector is
The 78511-118HLF: All 18 positions are populated. The contact material is phosphor bronze with gold or Gold GXT plating on the mating face at 30.0 µin (0.76 µm) thickness — thicker than a basic flash, which gives the part genuine reconnection duty rather than one-time press-fit use. The LCP insulation body carries a UL94 V-0 flammability rating and the operating window spans -65 °C to 125 °C, covering most industrial and telecom backplane environments without derating concerns at room temperature.
What the ratings mean for your BOM
18 positions is the key BOM match for this base product. Confirm your board expects all 18 pins driven; there is no partial-load option on this exact part number. Pitch is 0.100 inch / 2.54 mm — the most widely second-sourced header grid in the industry. Any 2.54 mm single-row header with 18 positions on the same pin length and board footprint is a potential cross, provided the insulation height (0.100 inch / 2.54 mm,) and overall contact length (0.538 inch / 13.67 mm,) also match for your connector stack.
Sourcing and lifecycle
The 78511-118HLF carries an Active product status — standard BOM demand, quoted to order against your quantity. No official successor order code is listed in the lifecycle record. The 2.54 mm header grid is one of the most widely second-sourced connector geometries in the industry; multiple manufacturers offer BERGSTIK-equivalent or pin-compatible 18-position single-row headers. Before committing, verify that the post length (0.120 inch / 3.05 mm,) and insulation height (0.100 inch / 2.54 mm,) match your board thickness and header socket to avoid stack height conflict.