diff --git a/src/core/include/mp-units/framework/unit_concepts.h b/src/core/include/mp-units/framework/unit_concepts.h
index bcc8aaf2..c36521a7 100644
--- a/src/core/include/mp-units/framework/unit_concepts.h
+++ b/src/core/include/mp-units/framework/unit_concepts.h
@@ -102,9 +102,6 @@ concept UnitOf = AssociatedUnit<U> && QuantitySpec<MP_UNITS_REMOVE_CONST(decltyp
 
 namespace detail {
 
-template<typename U, auto QS>
-concept UnitOf = UnitOf<U, QS>;
-
 template<typename U, auto QS>
 concept WeakUnitOf =
   Unit<U> && QuantitySpec<MP_UNITS_REMOVE_CONST(decltype(QS))> && ((!AssociatedUnit<U>) || UnitOf<U, QS>);