diff --git a/Project.toml b/Project.toml
index 028d514..ec930c4 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "ITensorBase"
 uuid = "4795dd04-0d67-49bb-8f44-b89c448a1dc7"
 authors = ["ITensor developers <support@itensor.org> and contributors"]
-version = "0.1.14"
+version = "0.1.15"
 
 [deps]
 Accessors = "7d9f7c33-5ae7-4f3b-8dc6-eff91059b697"
@@ -16,10 +16,12 @@ VectorInterface = "409d34a3-91d5-4945-b6ec-7529ddf182d8"
 
 [weakdeps]
 DiagonalArrays = "74fd4be6-21e2-4f6f-823a-4360d37c7a77"
+GradedUnitRanges = "e2de450a-8a67-46c7-b59c-01d5a3d041c5"
 SparseArraysBase = "0d5efcca-f356-4864-8770-e1ed8d78f208"
 
 [extensions]
 ITensorBaseDiagonalArraysExt = "DiagonalArrays"
+ITensorBaseGradedUnitRangesExt = "GradedUnitRanges"
 ITensorBaseSparseArraysBaseExt = ["NamedDimsArrays", "SparseArraysBase"]
 
 [compat]
@@ -27,6 +29,7 @@ Accessors = "0.1.39"
 DerivableInterfaces = "0.3.7"
 DiagonalArrays = "0.2.3"
 FillArrays = "1.13.0"
+GradedUnitRanges = "0.1.4"
 LinearAlgebra = "1.10"
 MapBroadcast = "0.1.5"
 NamedDimsArrays = "0.4"
diff --git a/ext/ITensorBaseGradedUnitRangesExt/ITensorBaseGradedUnitRangesExt.jl b/ext/ITensorBaseGradedUnitRangesExt/ITensorBaseGradedUnitRangesExt.jl
new file mode 100644
index 0000000..98a02b2
--- /dev/null
+++ b/ext/ITensorBaseGradedUnitRangesExt/ITensorBaseGradedUnitRangesExt.jl
@@ -0,0 +1,10 @@
+module ITensorBaseGradedUnitRangesExt
+
+using GradedUnitRanges: AbstractGradedUnitRange
+using ITensorBase: ITensorBase
+
+# TODO: Replace with a more general functionality in
+# `GradedUnitRanges`, like `isgraded`.
+ITensorBase.hasqns(r::AbstractGradedUnitRange) = true
+
+end
diff --git a/src/quirks.jl b/src/quirks.jl
index e290280..9674e1a 100644
--- a/src/quirks.jl
+++ b/src/quirks.jl
@@ -1,9 +1,4 @@
-# TODO: Define this properly.
-# TODO: Rename this to `dual`.
-dag(i::Index) = i
-# TODO: Define this properly.
-# TODO: Rename this to `dual`.
-dag(a::ITensor) = a
+using NamedDimsArrays: dename
 
 # TODO: Deprecate, just use `Int(length(i))` or
 # `unname(length(i))` directly.
@@ -15,12 +10,11 @@ dim(i::Index) = Int(length(i))
 # `unname(length(i))` directly.
 dim(a::AbstractITensor) = Int(length(a))
 
-# TODO: Define this properly.
-# TODO: Maybe rename to `isgraded(i::Index) = isgraded(dename(i))`.
-hasqns(::Index) = false
-# TODO: Define this properly.
-# TODO: Maybe rename to `isgraded(a) = all(isgraded, axes(a))`.
-hasqns(::AbstractITensor) = false
+# TODO: Replace with a more general functionality in
+# `GradedUnitRanges`, like `isgraded`.
+hasqns(r::AbstractUnitRange) = false
+hasqns(i::Index) = hasqns(dename(i))
+hasqns(a::AbstractITensor) = all(hasqns, inds(a))
 
 # This seems to be needed to get broadcasting working.
 # TODO: Investigate this and see if we can get rid of it.
diff --git a/test/Project.toml b/test/Project.toml
index fce2cd3..4f5767e 100644
--- a/test/Project.toml
+++ b/test/Project.toml
@@ -1,12 +1,16 @@
 [deps]
 Aqua = "4c88cf16-eb10-579e-8560-4a9242c79595"
+BlockArrays = "8e7c35d0-a365-5155-bbbb-fb81a777f24e"
+BlockSparseArrays = "2c9a651f-6452-4ace-a6ac-809f4280fbb4"
 DiagonalArrays = "74fd4be6-21e2-4f6f-823a-4360d37c7a77"
+GradedUnitRanges = "e2de450a-8a67-46c7-b59c-01d5a3d041c5"
 ITensorBase = "4795dd04-0d67-49bb-8f44-b89c448a1dc7"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 NamedDimsArrays = "60cbd0c0-df58-4cb7-918c-6f5607b73fde"
 SafeTestsets = "1bc83da4-3b8d-516f-aca4-4fe02f6d838f"
 SparseArraysBase = "0d5efcca-f356-4864-8770-e1ed8d78f208"
 Suppressor = "fd094767-a336-5f1f-9728-57cf17d0bbfb"
+SymmetrySectors = "f8a8ad64-adbc-4fce-92f7-ffe2bb36a86e"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [compat]
diff --git a/test/test_basics.jl b/test/test_basics.jl
index b19c892..376d8c9 100644
--- a/test/test_basics.jl
+++ b/test/test_basics.jl
@@ -1,8 +1,23 @@
-using ITensorBase:
-  ITensorBase, ITensor, Index, gettag, hastag, inds, plev, prime, settag, tags, unsettag
+using BlockArrays: Block
+using BlockSparseArrays: BlockSparseArray
 using DiagonalArrays: δ, delta, diagview
+using GradedUnitRanges: dual, gradedrange
+using ITensorBase:
+  ITensorBase,
+  ITensor,
+  Index,
+  gettag,
+  hastag,
+  hasqns,
+  inds,
+  plev,
+  prime,
+  settag,
+  tags,
+  unsettag
 using NamedDimsArrays: dename, name, named
 using SparseArraysBase: oneelement
+using SymmetrySectors: U1
 using Test: @test, @test_broken, @testset
 
 @testset "ITensorBase" begin
@@ -75,4 +90,23 @@ using Test: @test, @test_broken, @testset
     @test a[2] == 1
     @test a[3] == 0
   end
+  @testset "hasqns" begin
+    i = Index(2)
+    j = Index(2)
+    a = ITensor(randn(2, 2), (i, j))
+    @test !hasqns(i)
+    @test !hasqns(j)
+    @test !hasqns(a)
+
+    r = gradedrange([U1(0) => 2, U1(1) => 2])
+    d = BlockSparseArray{Float64}(r, dual(r))
+    d[Block(1, 1)] = randn(2, 2)
+    d[Block(2, 2)] = randn(2, 2)
+    i = Index(r)
+    j = Index(dual(r))
+    a = ITensor(d, (i, j))
+    @test hasqns(i)
+    @test hasqns(j)
+    @test hasqns(a)
+  end
 end