diff --git a/include/xo/unit/Quantity2.hpp b/include/xo/unit/Quantity2.hpp
index afebb074..b44bf0f0 100644
--- a/include/xo/unit/Quantity2.hpp
+++ b/include/xo/unit/Quantity2.hpp
@@ -10,7 +10,7 @@
 #include "unit2.hpp"
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         /** @class quantity
          *  @brief represent a scalar quantity with attached units.  enforce dimensional consistency.
          *
@@ -87,7 +87,7 @@ namespace xo {
         {
             return Quantity::multiply(x, y);
         }
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 
diff --git a/include/xo/unit/Quantity2_iostream.hpp b/include/xo/unit/Quantity2_iostream.hpp
index 0a1f2893..2c1aa55a 100644
--- a/include/xo/unit/Quantity2_iostream.hpp
+++ b/include/xo/unit/Quantity2_iostream.hpp
@@ -9,7 +9,7 @@
 #include <iostream>
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         template <typename Repr = double,
                   typename Int = std::int64_t>
         inline std::ostream &
@@ -23,7 +23,7 @@ namespace xo {
 
             return os;
         }
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 /** end Quantity2_iostream.hpp **/
diff --git a/include/xo/unit/basis_unit2.hpp b/include/xo/unit/basis_unit2.hpp
index ae6d35d5..828e4fd5 100644
--- a/include/xo/unit/basis_unit2.hpp
+++ b/include/xo/unit/basis_unit2.hpp
@@ -8,7 +8,7 @@
 #include <vector>
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         using basis_unit2_abbrev_type = flatstring<16>;
 
         using scalefactor_ratio_type = xo::ratio::ratio<std::int64_t>;
@@ -365,7 +365,7 @@ namespace xo {
             constexpr auto scaled_native_unit2_abbrev_v = scaled_native_unit2_abbrev<BasisDim, InnerScaleNum, InnerScaleDen>::value;
         }
 
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 
diff --git a/include/xo/unit/bpu_store.hpp b/include/xo/unit/bpu_store.hpp
index b66fcd51..196bd8ed 100644
--- a/include/xo/unit/bpu_store.hpp
+++ b/include/xo/unit/bpu_store.hpp
@@ -5,7 +5,7 @@
 #include "native_bpu2.hpp"
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         /** @class basis_unit2_store
          *  @brief Store known basis units for runtime
          **/
@@ -156,7 +156,7 @@ namespace xo {
             /* bu_abbrev_v[dim] holds known units for native unit dim */
             std::vector<native_scale_v> bu_abbrev_vv_;
         };
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 /** end bpu_store.hpp **/
diff --git a/include/xo/unit/dim_iostream.hpp b/include/xo/unit/dim_iostream.hpp
index 24b31326..c420bca1 100644
--- a/include/xo/unit/dim_iostream.hpp
+++ b/include/xo/unit/dim_iostream.hpp
@@ -9,13 +9,13 @@
 #include <iostream>
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         inline std::ostream &
         operator<<(std::ostream & os, dim x) {
             os << dim2str(x);
             return os;
         }
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 /** end dim_iostream.hpp **/
diff --git a/include/xo/unit/dim_util.hpp b/include/xo/unit/dim_util.hpp
index 7d369bc2..b3b9a365 100644
--- a/include/xo/unit/dim_util.hpp
+++ b/include/xo/unit/dim_util.hpp
@@ -7,7 +7,7 @@
 #include <cstdint>
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         enum class dim {
             invalid = -1,
 
@@ -76,7 +76,7 @@ namespace xo {
         template <dim Dim>
         constexpr auto native_unit_for_v = native_unit_for<Dim>::value;
 
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 /* end dim_util.hpp */
diff --git a/include/xo/unit/dim_util2.hpp b/include/xo/unit/dim_util2.hpp
index c49706fd..709056cd 100644
--- a/include/xo/unit/dim_util2.hpp
+++ b/include/xo/unit/dim_util2.hpp
@@ -9,7 +9,7 @@
 #include "xo/flatstring/flatstring.hpp"
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         using native_unit2_abbrev_type = flatstring<8>;
 
         /** @class native_unit2
@@ -43,7 +43,7 @@ namespace xo {
             native_unit2(dim::price,    native_unit2_abbrev_type::from_chars("px")),
         };
 
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 
diff --git a/include/xo/unit/native_bpu2.hpp b/include/xo/unit/native_bpu2.hpp
index 62786d44..cbd52bb2 100644
--- a/include/xo/unit/native_bpu2.hpp
+++ b/include/xo/unit/native_bpu2.hpp
@@ -10,7 +10,7 @@
 #include "dim_iostream.hpp"
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         using bpu2_abbrev_type = flatstring<24>;
 
         using power_ratio_type = xo::ratio::ratio<std::int64_t>;
@@ -126,7 +126,7 @@ namespace xo {
                       flatstring_from_exponent<PowerNum, PowerDen>())));
         };
 #endif
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 
diff --git a/include/xo/unit/native_bpu2_iostream.hpp b/include/xo/unit/native_bpu2_iostream.hpp
index a748670c..e16cc65a 100644
--- a/include/xo/unit/native_bpu2_iostream.hpp
+++ b/include/xo/unit/native_bpu2_iostream.hpp
@@ -10,7 +10,7 @@
 #include <iostream>
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         template <typename Int>
         inline std::ostream &
         operator<<(std::ostream & os, const bpu2<Int> & x) {
@@ -22,7 +22,7 @@ namespace xo {
 
             return os;
         }
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 
diff --git a/include/xo/unit/natural_unit.hpp b/include/xo/unit/natural_unit.hpp
index ecfea289..d827cfca 100644
--- a/include/xo/unit/natural_unit.hpp
+++ b/include/xo/unit/natural_unit.hpp
@@ -10,7 +10,7 @@
 #include <cassert>
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         /** @class natural_unit
          *  @brief an array representing the cartesian product of distinct basis-power-units
          *
@@ -223,7 +223,7 @@ namespace xo {
             constexpr auto nanogram = bpu_array_maker<std::int64_t>::make_bpu_array(make_unit_power<std::int64_t>(bu2::nanogram));
             constexpr auto microgram = bpu_array_maker<std::int64_t>::make_bpu_array(make_unit_power<std::int64_t>(bu2::microgram));
         }
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 /** end natural_unit.hpp **/
diff --git a/include/xo/unit/natural_unit_iostream.hpp b/include/xo/unit/natural_unit_iostream.hpp
index 931d8f22..99d3dd4d 100644
--- a/include/xo/unit/natural_unit_iostream.hpp
+++ b/include/xo/unit/natural_unit_iostream.hpp
@@ -9,7 +9,7 @@
 #include <iostream>
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         template <typename Int>
         inline std::ostream &
         operator<<(std::ostream & os, const natural_unit<Int> & x) {
@@ -22,7 +22,7 @@ namespace xo {
             os << "]>";
             return os;
         }
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 /** end natural_unit_iostream.hpp **/
diff --git a/include/xo/unit/numeric_concept.hpp b/include/xo/unit/numeric_concept.hpp
index f1d32f58..b853e8f5 100644
--- a/include/xo/unit/numeric_concept.hpp
+++ b/include/xo/unit/numeric_concept.hpp
@@ -5,7 +5,7 @@
 #include <concepts>
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         /** @concept numeric_concept
          *  @brief Concept for values that participate in arithmetic operations (+,-,*,/) and comparisons
          *
@@ -28,7 +28,7 @@ namespace xo {
             { x == y };
             { x != y };
         };
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 /* end numeric_concept.hpp */
diff --git a/include/xo/unit/quantity2.hpp b/include/xo/unit/quantity2.hpp
index 9fb74ac2..efd2b75f 100644
--- a/include/xo/unit/quantity2.hpp
+++ b/include/xo/unit/quantity2.hpp
@@ -8,7 +8,7 @@
 #include "bpu_array.hpp"
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         /** @class quantity
          *  @brief represent a scalar quantity with attached units.  enforce dimensional consistency.
          *
@@ -21,7 +21,7 @@ namespace xo {
 
         private:
         };
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 
diff --git a/include/xo/unit/quantity2_concept.hpp b/include/xo/unit/quantity2_concept.hpp
index b401be7b..3fbde14e 100644
--- a/include/xo/unit/quantity2_concept.hpp
+++ b/include/xo/unit/quantity2_concept.hpp
@@ -6,7 +6,7 @@
 #include "numeric_concept.hpp"
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         template <typename Quantity>
         concept quantity2_concept = requires(Quantity qty, typename Quantity::repr_type repr)
         {
@@ -19,5 +19,5 @@ namespace xo {
             //{ Quantity::promote(repr) } -> std::same_as<Quantity>;
         } && (true //unit_concept<typename Quantity::unit_type>
               && numeric_concept<typename Quantity::repr_type>);
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
diff --git a/include/xo/unit/scaled_unit2.hpp b/include/xo/unit/scaled_unit2.hpp
index c6655a3e..d8c11bdd 100644
--- a/include/xo/unit/scaled_unit2.hpp
+++ b/include/xo/unit/scaled_unit2.hpp
@@ -9,7 +9,7 @@
 //#include <cstdint>
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         /** @class bpu2_array_rescale_result
          *  @brief Represents the product sqrt(outer_scale_sq) * outer_scale_exact * nat_unit
          **/
@@ -120,7 +120,7 @@ namespace xo {
                      rr.outer_scale_exact_ * x_unit.outer_scale_exact_ * y_unit.outer_scale_exact_,
                      rr.outer_scale_sq_ * x_unit.outer_scale_sq_ * y_unit.outer_scale_sq_));
         }
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 /** end scaled_unit2.hpp **/
diff --git a/include/xo/unit/scaled_unit_iostream.hpp b/include/xo/unit/scaled_unit_iostream.hpp
index 64525991..4d0ab1fe 100644
--- a/include/xo/unit/scaled_unit_iostream.hpp
+++ b/include/xo/unit/scaled_unit_iostream.hpp
@@ -9,7 +9,7 @@
 #include <iostream>
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         template <typename Int>
         inline std::ostream &
         operator<<(std::ostream & os, const scaled_unit2<Int> & x) {
@@ -21,7 +21,7 @@ namespace xo {
 
             return os;
         };
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 /** end scaled_unit_iostream.hpp **/
diff --git a/include/xo/unit/unit2.hpp b/include/xo/unit/unit2.hpp
index 3fe9b622..eab1bf8f 100644
--- a/include/xo/unit/unit2.hpp
+++ b/include/xo/unit/unit2.hpp
@@ -8,7 +8,7 @@
 #include "natural_unit.hpp"
 
 namespace xo {
-    namespace unit {
+    namespace qty {
         /** @class unit2
          *  @brief represent an arbitrary unit along with dimension details
          *
@@ -18,7 +18,7 @@ namespace xo {
          **/
         template <typename Int>
         using unit2 = natural_unit<Int>;
-    } /*namespace unit*/
+    } /*namespace qty*/
 } /*namespace xo*/
 
 /** end unit2.hpp **/
diff --git a/utest/mpl_unit.test.cpp b/utest/mpl_unit.test.cpp
index 680fad65..0fc6e10f 100644
--- a/utest/mpl_unit.test.cpp
+++ b/utest/mpl_unit.test.cpp
@@ -39,7 +39,7 @@ namespace xo {
         //using xo::unit::bpu2_abbrev_type;
         //using xo::unit::abbrev::bpu2_abbrev;
         //using xo::unit::basis_unit2_store;
-        using xo::unit::power_ratio_type;
+        using xo::qty::power_ratio_type;
         //using xo::unit::abbrev::flatstring_from_exponent;
         //using xo::unit::bpu2;
         //using xo::unit::detail::bpu2_rescale;
diff --git a/utest/unit.test.cpp b/utest/unit.test.cpp
index 451fadcc..c957ce9c 100644
--- a/utest/unit.test.cpp
+++ b/utest/unit.test.cpp
@@ -23,57 +23,31 @@ namespace xo {
 
         using xo::reflect::Reflect;
 
-        namespace su2 = xo::unit::su2;
+        namespace su2 = xo::qty::su2;
 
-        using xo::unit::Quantity2;
-        using xo::unit::dim;
-        using xo::unit::basis_unit2_abbrev_type;
-        using xo::unit::native_unit2;
-        using xo::unit::native_unit2_v;
-        using xo::unit::scalefactor_ratio_type;
-        using xo::unit::units::scaled_native_unit2_abbrev;
-        using xo::unit::units::scaled_native_unit2_abbrev_v;
-        using xo::unit::basis_unit2;
-        using xo::unit::abbrev::basis_unit2_abbrev;;
-        using xo::unit::bpu2_abbrev_type;
-        using xo::unit::abbrev::bpu2_abbrev;
-        using xo::unit::basis_unit2_store;
-        using xo::unit::power_ratio_type;
-        using xo::unit::abbrev::flatstring_from_exponent;
-        using xo::unit::bpu2;
-        using xo::unit::detail::bpu2_rescale;
-        using xo::unit::detail::bpu2_product;
-        using xo::unit::natural_unit;
-        using xo::unit::bpu_array_maker;
-        using xo::unit::detail::nu_product;
-        using xo::unit::unit_qty;
+        using xo::qty::Quantity2;
+        using xo::qty::dim;
+        using xo::qty::basis_unit2_abbrev_type;
+        using xo::qty::native_unit2;
+        using xo::qty::native_unit2_v;
+        using xo::qty::scalefactor_ratio_type;
+        using xo::qty::units::scaled_native_unit2_abbrev;
+        using xo::qty::units::scaled_native_unit2_abbrev_v;
+        using xo::qty::basis_unit2;
+        using xo::qty::abbrev::basis_unit2_abbrev;;
+        using xo::qty::bpu2_abbrev_type;
+        using xo::qty::abbrev::bpu2_abbrev;
+        using xo::qty::basis_unit2_store;
+        using xo::qty::power_ratio_type;
+        using xo::qty::abbrev::flatstring_from_exponent;
+        using xo::qty::bpu2;
+        using xo::qty::detail::bpu2_rescale;
+        using xo::qty::detail::bpu2_product;
+        using xo::qty::natural_unit;
+        using xo::qty::bpu_array_maker;
+        using xo::qty::detail::nu_product;
+        using xo::qty::unit_qty;
 
-        //using xo::unit::native_unit_abbrev_v;
-        //using xo::unit::units::scaled_native_unit_abbrev_v;
-        //using xo::unit::native_dim_abbrev;
-        //using xo::unit::stringliteral_compare;
-        //using xo::unit::literal_size_v;
-        //using xo::unit::stringliteral_from_digit;
-        //using xo::unit::stringliteral_from_int_v;
-        //using xo::unit::stringliteral;
-#ifndef __clang__
-        //using xo::unit::stringliteral_concat;
-        //using xo::unit::stringliteral_from_ratio;
-        //using xo::unit::bpu_assemble_abbrev_helper;
-        //using xo::unit::bpu_assemble_abbrev;
-#endif
-        //using xo::unit::bpu_node;
-        //using xo::unit::wrap_unit;
-        //using xo::unit::unit_abbrev_v;
-        //using xo::unit::dim_abbrev_v;
-        //using xo::unit::di_cartesian_product;
-        //using xo::unit::di_cartesian_product1;
-        //using xo::unit::unit_cartesian_product_t;
-        //using xo::unit::bpu_cartesian_product;
-        //using xo::unit::bpu_cartesian_product_helper;
-        //using xo::unit::unit_invert_t;
-        //using xo::unit::units::gram;
-        //using xo::unit::units::second;
         using xo::print::ccs;
 
         template <typename T>
@@ -206,7 +180,7 @@ namespace xo {
 
             log && log(xtag("price",            scaled_native_unit2_abbrev_v<dim::price>));
 
-            REQUIRE(xo::unit::units::scaled_native_unit2_abbrev<dim::mass>::value == xo::flatstring("g"));
+            REQUIRE(xo::qty::units::scaled_native_unit2_abbrev<dim::mass>::value == xo::flatstring("g"));
 
             /* proof that scaled_native_unit2_abbrev::value is constexpr */
             static_assert(scaled_native_unit2_abbrev_v<dim::mass>