diff --git a/NDTensors/src/lib/GradedAxes/src/dual.jl b/NDTensors/src/lib/GradedAxes/src/dual.jl
index 28f140d69e..ca985e30a0 100644
--- a/NDTensors/src/lib/GradedAxes/src/dual.jl
+++ b/NDTensors/src/lib/GradedAxes/src/dual.jl
@@ -5,6 +5,8 @@ isdual(::AbstractUnitRange) = false
 
 using NDTensors.LabelledNumbers:
   LabelledStyle, IsLabelled, NotLabelled, label, labelled, unlabel
+
+dual(i::LabelledInteger) = labelled(unlabel(i), dual(label(i)))
 label_dual(x) = label_dual(LabelledStyle(x), x)
 label_dual(::NotLabelled, x) = x
 label_dual(::IsLabelled, x) = labelled(unlabel(x), dual(label(x)))
diff --git a/NDTensors/src/lib/GradedAxes/src/gradedunitrangedual.jl b/NDTensors/src/lib/GradedAxes/src/gradedunitrangedual.jl
index 1ffee324fc..c6d79495a5 100644
--- a/NDTensors/src/lib/GradedAxes/src/gradedunitrangedual.jl
+++ b/NDTensors/src/lib/GradedAxes/src/gradedunitrangedual.jl
@@ -104,8 +104,6 @@ end
 Base.unitrange(a::GradedUnitRangeDual) = a
 
 using NDTensors.LabelledNumbers: LabelledInteger, label, labelled, unlabel
-dual(i::LabelledInteger) = labelled(unlabel(i), dual(label(i)))
-
 using BlockArrays: BlockArrays, blockaxes, blocklasts, combine_blockaxes, findblock
 BlockArrays.blockaxes(a::GradedUnitRangeDual) = blockaxes(nondual(a))
 BlockArrays.blockfirsts(a::GradedUnitRangeDual) = label_dual.(blockfirsts(nondual(a)))
diff --git a/NDTensors/src/lib/GradedAxes/test/test_dual.jl b/NDTensors/src/lib/GradedAxes/test/test_dual.jl
index 04203961a7..714dd04b7a 100644
--- a/NDTensors/src/lib/GradedAxes/test/test_dual.jl
+++ b/NDTensors/src/lib/GradedAxes/test/test_dual.jl
@@ -12,6 +12,7 @@ using BlockArrays:
   blocks,
   findblock
 using NDTensors.GradedAxes:
+  AbstractGradedUnitRange,
   GradedAxes,
   GradedUnitRangeDual,
   OneToOne,
@@ -60,6 +61,7 @@ end
       [gradedrange([U1(0) => 2, U1(1) => 3]), gradedrange([U1(0) => 2, U1(1) => 3])[1:5]]
     ad = dual(a)
     @test ad isa GradedUnitRangeDual
+    @test ad isa AbstractGradedUnitRange
     @test eltype(ad) == LabelledInteger{Int,U1}
     @test blocklengths(ad) isa Vector
     @test eltype(blocklengths(ad)) == eltype(blocklengths(a))
@@ -78,6 +80,8 @@ end
     @test blocklasts(ad) == [labelled(2, U1(0)), labelled(5, U1(-1))]
     @test blocklength(ad) == 2
     @test blocklengths(ad) == [2, 3]
+    @test blocklabels(ad) == [U1(0), U1(-1)]
+    @test label.(blocklengths(ad)) == [U1(0), U1(-1)]
     @test findblock(ad, 4) == Block(2)
     @test only(blockaxes(ad)) == Block(1):Block(2)
     @test blocks(ad) == [labelled(1:2, U1(0)), labelled(3:5, U1(-1))]