Use the complete construction
A two-piece set is wool-free only if every included layer is. The Injinji Liner + Hiker here includes wool in its outer, so a synthetic inner cannot qualify the full system.
Alpaca is also an animal fiber. The PAKA Trail Crew is excluded from these wool-free choices even though its label uses the word alpaca rather than merino.
Three different ways to wear synthetics
The current matching set includes Injinji’s five-toe Trail Midweight Crew, Wrightsock’s double-layer Adventure Crew and Feetures’ anatomical Trail Max Mini Crew. Compare those structural differences before using material alone to choose.
Keep the Feetures percentage conflict visible
The current Feetures sources disagree on the precise polyester/nylon percentages. Both observed compositions are synthetic, so the wool-free fact remains distinct from the unresolved percentages. Check the exact variant label before relying on a specific blend.
Why the Coolmax Hiker is not in this exact filter
Darn Tough describes the US 1931 as vegan, but this record does not have a settled exact US composition. We preserve that manufacturer statement on its profile and keep the incomplete material record out of a strict wool-free match.
Wool-free is not a medical answer
This filter identifies material content, not a diagnosis or a promise about skin response. Also distinguish a wool-free label from a broader vegan claim, which needs its own explicit manufacturer statement.