14.0 mm compressed height — the dimension that sets the stack
The Z01U-4G7L1-11000-E000 is a single-circuit spring-loaded contact from Amphenol ICC (FCI), built for board-to-board or test-fixture applications where a defined compressed height of 14.0 mm is required. The stainless steel spring provides the mechanical memory to maintain contact force through thermal cycling and vibration — a copper-alloy spring would take a set under the same duty. Non-gendered design means the same part number can be used on both the top and bottom board, simplifying the BOM and reducing inventory lines.
Stainless steel vs copper alloy — material choice matters
Compared to the Z02D-4F7L1-11000-E000, which uses a copper-alloy spring, the Z01U-4G7L1-11000-E000 uses stainless steel. Stainless steel gives better corrosion resistance and mechanical memory over temperature, but at a slightly lower conductivity than copper alloy. For a signal-only path, the conductivity difference is irrelevant; for a power path, the copper-alloy sibling carries more current for the same temperature rise. The Z01B-4G7L1-11000-E000 carries flash gold instead of the 8.00 µin thickness on this part. Flash gold is adequate for a few dozen mating cycles; the 8.00 µin on the Z01U supports hundreds of cycles before the nickel underplate is exposed.
Surface-mount termination for automated assembly
The contact is terminated via surface mount, compatible with standard SMT pick-and-place and reflow processes.