diff --git a/src/systems/include/mp-units/systems/iec80000/binary_prefixes.h b/src/systems/include/mp-units/systems/iec80000/binary_prefixes.h
index ca3db21e5..112e71a8f 100644
--- a/src/systems/include/mp-units/systems/iec80000/binary_prefixes.h
+++ b/src/systems/include/mp-units/systems/iec80000/binary_prefixes.h
@@ -27,23 +27,23 @@
 namespace mp_units::iec80000 {
 
 // clang-format off
-template<PrefixableUnit auto U> struct kibi_ : prefixed_unit<"Ki", mag_power<2, 10>, U> {};
-template<PrefixableUnit auto U> struct mebi_ : prefixed_unit<"Mi", mag_power<2, 20>, U> {};
-template<PrefixableUnit auto U> struct gibi_ : prefixed_unit<"Gi", mag_power<2, 30>, U> {};
-template<PrefixableUnit auto U> struct tebi_ : prefixed_unit<"Ti", mag_power<2, 40>, U> {};
-template<PrefixableUnit auto U> struct pebi_ : prefixed_unit<"Pi", mag_power<2, 50>, U> {};
-template<PrefixableUnit auto U> struct exbi_ : prefixed_unit<"Ei", mag_power<2, 60>, U> {};
-template<PrefixableUnit auto U> struct zebi_ : prefixed_unit<"Zi", mag_power<2, 70>, U> {};
-template<PrefixableUnit auto U> struct yobi_ : prefixed_unit<"Yi", mag_power<2, 80>, U> {};
+template<PrefixableUnit U> struct kibi_ : prefixed_unit<"Ki", mag_power<2, 10>, U{}> {};
+template<PrefixableUnit U> struct mebi_ : prefixed_unit<"Mi", mag_power<2, 20>, U{}> {};
+template<PrefixableUnit U> struct gibi_ : prefixed_unit<"Gi", mag_power<2, 30>, U{}> {};
+template<PrefixableUnit U> struct tebi_ : prefixed_unit<"Ti", mag_power<2, 40>, U{}> {};
+template<PrefixableUnit U> struct pebi_ : prefixed_unit<"Pi", mag_power<2, 50>, U{}> {};
+template<PrefixableUnit U> struct exbi_ : prefixed_unit<"Ei", mag_power<2, 60>, U{}> {};
+template<PrefixableUnit U> struct zebi_ : prefixed_unit<"Zi", mag_power<2, 70>, U{}> {};
+template<PrefixableUnit U> struct yobi_ : prefixed_unit<"Yi", mag_power<2, 80>, U{}> {};
 
-template<PrefixableUnit auto U> inline constexpr kibi_<U> kibi;
-template<PrefixableUnit auto U> inline constexpr mebi_<U> mebi;
-template<PrefixableUnit auto U> inline constexpr gibi_<U> gibi;
-template<PrefixableUnit auto U> inline constexpr tebi_<U> tebi;
-template<PrefixableUnit auto U> inline constexpr pebi_<U> pebi;
-template<PrefixableUnit auto U> inline constexpr exbi_<U> exbi;
-template<PrefixableUnit auto U> inline constexpr zebi_<U> zebi;
-template<PrefixableUnit auto U> inline constexpr yobi_<U> yobi;
+template<PrefixableUnit auto U> inline constexpr kibi_<std::remove_const_t<decltype(U)>> kibi;
+template<PrefixableUnit auto U> inline constexpr mebi_<std::remove_const_t<decltype(U)>> mebi;
+template<PrefixableUnit auto U> inline constexpr gibi_<std::remove_const_t<decltype(U)>> gibi;
+template<PrefixableUnit auto U> inline constexpr tebi_<std::remove_const_t<decltype(U)>> tebi;
+template<PrefixableUnit auto U> inline constexpr pebi_<std::remove_const_t<decltype(U)>> pebi;
+template<PrefixableUnit auto U> inline constexpr exbi_<std::remove_const_t<decltype(U)>> exbi;
+template<PrefixableUnit auto U> inline constexpr zebi_<std::remove_const_t<decltype(U)>> zebi;
+template<PrefixableUnit auto U> inline constexpr yobi_<std::remove_const_t<decltype(U)>> yobi;
 // clang-format on
 
 }  // namespace mp_units::iec80000
diff --git a/src/systems/include/mp-units/systems/si/prefixes.h b/src/systems/include/mp-units/systems/si/prefixes.h
index f8c9431ca..09582df0d 100644
--- a/src/systems/include/mp-units/systems/si/prefixes.h
+++ b/src/systems/include/mp-units/systems/si/prefixes.h
@@ -27,55 +27,55 @@
 namespace mp_units::si {
 
 // clang-format off
-template<PrefixableUnit auto U> struct quecto_ : prefixed_unit<"q", mag_power<10, -30>, U> {};
-template<PrefixableUnit auto U> struct ronto_ : prefixed_unit<"r", mag_power<10, -27>, U> {};
-template<PrefixableUnit auto U> struct yocto_ : prefixed_unit<"y", mag_power<10, -24>, U> {};
-template<PrefixableUnit auto U> struct zepto_ : prefixed_unit<"z", mag_power<10, -21>, U> {};
-template<PrefixableUnit auto U> struct atto_  : prefixed_unit<"a", mag_power<10, -18>, U> {};
-template<PrefixableUnit auto U> struct femto_ : prefixed_unit<"f", mag_power<10, -15>, U> {};
-template<PrefixableUnit auto U> struct pico_  : prefixed_unit<"p", mag_power<10, -12>, U> {};
-template<PrefixableUnit auto U> struct nano_  : prefixed_unit<"n", mag_power<10, -9>, U> {};
-template<PrefixableUnit auto U> struct micro_ : prefixed_unit<basic_symbol_text{"µ", "u"}, mag_power<10, -6>, U> {};
-template<PrefixableUnit auto U> struct milli_ : prefixed_unit<"m", mag_power<10, -3>, U> {};
-template<PrefixableUnit auto U> struct centi_ : prefixed_unit<"c", mag_power<10, -2>, U> {};
-template<PrefixableUnit auto U> struct deci_  : prefixed_unit<"d", mag_power<10, -1>, U> {};
-template<PrefixableUnit auto U> struct deca_  : prefixed_unit<"da", mag_power<10, 1>, U> {};
-template<PrefixableUnit auto U> struct hecto_ : prefixed_unit<"h", mag_power<10, 2>, U> {};
-template<PrefixableUnit auto U> struct kilo_  : prefixed_unit<"k", mag_power<10, 3>, U> {};
-template<PrefixableUnit auto U> struct mega_  : prefixed_unit<"M", mag_power<10, 6>, U> {};
-template<PrefixableUnit auto U> struct giga_  : prefixed_unit<"G", mag_power<10, 9>, U> {};
-template<PrefixableUnit auto U> struct tera_  : prefixed_unit<"T", mag_power<10, 12>, U> {};
-template<PrefixableUnit auto U> struct peta_  : prefixed_unit<"P", mag_power<10, 15>, U> {};
-template<PrefixableUnit auto U> struct exa_   : prefixed_unit<"E", mag_power<10, 18>, U> {};
-template<PrefixableUnit auto U> struct zetta_ : prefixed_unit<"Z", mag_power<10, 21>, U> {};
-template<PrefixableUnit auto U> struct yotta_ : prefixed_unit<"Y", mag_power<10, 24>, U> {};
-template<PrefixableUnit auto U> struct ronna_ : prefixed_unit<"R", mag_power<10, 27>, U> {};
-template<PrefixableUnit auto U> struct quetta_ : prefixed_unit<"Q", mag_power<10, 30>, U> {};
+template<PrefixableUnit U> struct quecto_ : prefixed_unit<"q", mag_power<10, -30>, U{}> {};
+template<PrefixableUnit U> struct ronto_ : prefixed_unit<"r", mag_power<10, -27>, U{}> {};
+template<PrefixableUnit U> struct yocto_ : prefixed_unit<"y", mag_power<10, -24>, U{}> {};
+template<PrefixableUnit U> struct zepto_ : prefixed_unit<"z", mag_power<10, -21>, U{}> {};
+template<PrefixableUnit U> struct atto_  : prefixed_unit<"a", mag_power<10, -18>, U{}> {};
+template<PrefixableUnit U> struct femto_ : prefixed_unit<"f", mag_power<10, -15>, U{}> {};
+template<PrefixableUnit U> struct pico_  : prefixed_unit<"p", mag_power<10, -12>, U{}> {};
+template<PrefixableUnit U> struct nano_  : prefixed_unit<"n", mag_power<10, -9>, U{}> {};
+template<PrefixableUnit U> struct micro_ : prefixed_unit<basic_symbol_text{"µ", "u"}, mag_power<10, -6>, U{}> {};
+template<PrefixableUnit U> struct milli_ : prefixed_unit<"m", mag_power<10, -3>, U{}> {};
+template<PrefixableUnit U> struct centi_ : prefixed_unit<"c", mag_power<10, -2>, U{}> {};
+template<PrefixableUnit U> struct deci_  : prefixed_unit<"d", mag_power<10, -1>, U{}> {};
+template<PrefixableUnit U> struct deca_  : prefixed_unit<"da", mag_power<10, 1>, U{}> {};
+template<PrefixableUnit U> struct hecto_ : prefixed_unit<"h", mag_power<10, 2>, U{}> {};
+template<PrefixableUnit U> struct kilo_  : prefixed_unit<"k", mag_power<10, 3>, U{}> {};
+template<PrefixableUnit U> struct mega_  : prefixed_unit<"M", mag_power<10, 6>, U{}> {};
+template<PrefixableUnit U> struct giga_  : prefixed_unit<"G", mag_power<10, 9>, U{}> {};
+template<PrefixableUnit U> struct tera_  : prefixed_unit<"T", mag_power<10, 12>, U{}> {};
+template<PrefixableUnit U> struct peta_  : prefixed_unit<"P", mag_power<10, 15>, U{}> {};
+template<PrefixableUnit U> struct exa_   : prefixed_unit<"E", mag_power<10, 18>, U{}> {};
+template<PrefixableUnit U> struct zetta_ : prefixed_unit<"Z", mag_power<10, 21>, U{}> {};
+template<PrefixableUnit U> struct yotta_ : prefixed_unit<"Y", mag_power<10, 24>, U{}> {};
+template<PrefixableUnit U> struct ronna_ : prefixed_unit<"R", mag_power<10, 27>, U{}> {};
+template<PrefixableUnit U> struct quetta_ : prefixed_unit<"Q", mag_power<10, 30>, U{}> {};
 
-template<PrefixableUnit auto U> inline constexpr quecto_<U> quecto;
-template<PrefixableUnit auto U> inline constexpr ronto_<U> ronto;
-template<PrefixableUnit auto U> inline constexpr yocto_<U> yocto;
-template<PrefixableUnit auto U> inline constexpr zepto_<U> zepto;
-template<PrefixableUnit auto U> inline constexpr atto_<U> atto;
-template<PrefixableUnit auto U> inline constexpr femto_<U> femto;
-template<PrefixableUnit auto U> inline constexpr pico_<U> pico;
-template<PrefixableUnit auto U> inline constexpr nano_<U> nano;
-template<PrefixableUnit auto U> inline constexpr micro_<U> micro;
-template<PrefixableUnit auto U> inline constexpr milli_<U> milli;
-template<PrefixableUnit auto U> inline constexpr centi_<U> centi;
-template<PrefixableUnit auto U> inline constexpr deci_<U> deci;
-template<PrefixableUnit auto U> inline constexpr deca_<U> deca;
-template<PrefixableUnit auto U> inline constexpr hecto_<U> hecto;
-template<PrefixableUnit auto U> inline constexpr kilo_<U> kilo;
-template<PrefixableUnit auto U> inline constexpr mega_<U> mega;
-template<PrefixableUnit auto U> inline constexpr giga_<U> giga;
-template<PrefixableUnit auto U> inline constexpr tera_<U> tera;
-template<PrefixableUnit auto U> inline constexpr peta_<U> peta;
-template<PrefixableUnit auto U> inline constexpr exa_<U> exa;
-template<PrefixableUnit auto U> inline constexpr zetta_<U> zetta;
-template<PrefixableUnit auto U> inline constexpr yotta_<U> yotta;
-template<PrefixableUnit auto U> inline constexpr ronna_<U> ronna;
-template<PrefixableUnit auto U> inline constexpr quetta_<U> quetta;
+template<PrefixableUnit auto U> inline constexpr quecto_<std::remove_const_t<decltype(U)>> quecto;
+template<PrefixableUnit auto U> inline constexpr ronto_<std::remove_const_t<decltype(U)>> ronto;
+template<PrefixableUnit auto U> inline constexpr yocto_<std::remove_const_t<decltype(U)>> yocto;
+template<PrefixableUnit auto U> inline constexpr zepto_<std::remove_const_t<decltype(U)>> zepto;
+template<PrefixableUnit auto U> inline constexpr atto_<std::remove_const_t<decltype(U)>> atto;
+template<PrefixableUnit auto U> inline constexpr femto_<std::remove_const_t<decltype(U)>> femto;
+template<PrefixableUnit auto U> inline constexpr pico_<std::remove_const_t<decltype(U)>> pico;
+template<PrefixableUnit auto U> inline constexpr nano_<std::remove_const_t<decltype(U)>> nano;
+template<PrefixableUnit auto U> inline constexpr micro_<std::remove_const_t<decltype(U)>> micro;
+template<PrefixableUnit auto U> inline constexpr milli_<std::remove_const_t<decltype(U)>> milli;
+template<PrefixableUnit auto U> inline constexpr centi_<std::remove_const_t<decltype(U)>> centi;
+template<PrefixableUnit auto U> inline constexpr deci_<std::remove_const_t<decltype(U)>> deci;
+template<PrefixableUnit auto U> inline constexpr deca_<std::remove_const_t<decltype(U)>> deca;
+template<PrefixableUnit auto U> inline constexpr hecto_<std::remove_const_t<decltype(U)>> hecto;
+template<PrefixableUnit auto U> inline constexpr kilo_<std::remove_const_t<decltype(U)>> kilo;
+template<PrefixableUnit auto U> inline constexpr mega_<std::remove_const_t<decltype(U)>> mega;
+template<PrefixableUnit auto U> inline constexpr giga_<std::remove_const_t<decltype(U)>> giga;
+template<PrefixableUnit auto U> inline constexpr tera_<std::remove_const_t<decltype(U)>> tera;
+template<PrefixableUnit auto U> inline constexpr peta_<std::remove_const_t<decltype(U)>> peta;
+template<PrefixableUnit auto U> inline constexpr exa_<std::remove_const_t<decltype(U)>> exa;
+template<PrefixableUnit auto U> inline constexpr zetta_<std::remove_const_t<decltype(U)>> zetta;
+template<PrefixableUnit auto U> inline constexpr yotta_<std::remove_const_t<decltype(U)>> yotta;
+template<PrefixableUnit auto U> inline constexpr ronna_<std::remove_const_t<decltype(U)>> ronna;
+template<PrefixableUnit auto U> inline constexpr quetta_<std::remove_const_t<decltype(U)>> quetta;
 // clang-format on
 
 }  // namespace mp_units::si
diff --git a/test/static/unit_test.cpp b/test/static/unit_test.cpp
index d187467a0..6b3ab4d1c 100644
--- a/test/static/unit_test.cpp
+++ b/test/static/unit_test.cpp
@@ -212,8 +212,8 @@ static_assert(convertible(kilojoule, joule));
 static_assert(kilojoule != joule);
 static_assert(kilojoule.symbol == "kJ");
 
-static_assert(is_of_type<si::kilo<metre>, si::kilo_<metre>>);
-static_assert(is_of_type<si::kilo<joule>, si::kilo_<joule>>);
+static_assert(is_of_type<si::kilo<metre>, si::kilo_<metre_>>);
+static_assert(is_of_type<si::kilo<joule>, si::kilo_<joule_>>);
 
 // TODO Should the below be a scaled version of metre^2?
 static_assert(is_of_type<kilometre * metre, derived_unit<kilometre_, metre_>>);       // !!!
@@ -264,7 +264,7 @@ static_assert(is_of_type<get_canonical_unit(km_2).reference_unit, metre_>);
 static_assert(get_canonical_unit(km_2).mag == mag<2000>);
 
 constexpr auto kJ_42 = mag<42> * si::kilo<joule>;
-static_assert(is_of_type<kJ_42, scaled_unit<mag<42>, si::kilo_<joule>>>);
+static_assert(is_of_type<kJ_42, scaled_unit<mag<42>, si::kilo_<joule_>>>);
 static_assert(
   is_of_type<get_canonical_unit(kJ_42).reference_unit, derived_unit<gram_, power<metre_, 2>, per<power<second_, 2>>>>);
 static_assert(get_canonical_unit(kJ_42).mag == mag<42'000'000>);
@@ -467,7 +467,7 @@ static_assert(!convertible(metre, metre* metre));
 
 // one
 static_assert(is_of_type<metre / metre, one_>);
-static_assert(is_of_type<si::kilo<metre> / metre, derived_unit<si::kilo_<metre>, per<metre_>>>);
+static_assert(is_of_type<si::kilo<metre> / metre, derived_unit<si::kilo_<metre_>, per<metre_>>>);
 static_assert(metre / metre == one);
 static_assert(hertz * second == one);
 static_assert(one * one == one);
@@ -509,7 +509,7 @@ static_assert(is_of_type<pow<1, 2>(metre / (second * second)), derived_unit<powe
 static_assert(is_of_type<kilometre * kilometre, derived_unit<power<kilometre_, 2>>>);
 
 static_assert(is_of_type<pow<2>(kilometre), derived_unit<power<kilometre_, 2>>>);
-static_assert(is_of_type<pow<2>(si::kilo<metre>), derived_unit<power<si::kilo_<metre>, 2>>>);
+static_assert(is_of_type<pow<2>(si::kilo<metre>), derived_unit<power<si::kilo_<metre_>, 2>>>);
 static_assert(is_of_type<pow<2>(hour), derived_unit<power<hour_, 2>>>);
 static_assert(
   is_of_type<pow<2>(mag<3600>* second), scaled_unit<mag<3600> * mag<3600>, derived_unit<power<second_, 2>>>>);