diff --git a/src/core_types.jl b/src/core_types.jl
index 5238987..4a3c9f4 100644
--- a/src/core_types.jl
+++ b/src/core_types.jl
@@ -6,9 +6,6 @@ unitary (orthogonal) `N`×`N` matrices.
 """
 abstract type Rotation{N,T} <: StaticMatrix{N,N,T} end
 
-Base.@pure StaticArrays.Size(::Type{Rotation{N}}) where {N} = Size(N,N)
-Base.@pure StaticArrays.Size(::Type{Rotation{N,T}}) where {N,T} = Size(N,N)
-Base.@pure StaticArrays.Size(::Type{R}) where {R<:Rotation} = Size(supertype(R))
 Base.adjoint(r::Rotation) = inv(r)
 Base.transpose(r::Rotation{N,T}) where {N,T<:Real} = inv(r)
 Base.real(R::Type{<:Rotation}) = R
diff --git a/src/rotation_generator.jl b/src/rotation_generator.jl
index f18c700..9d13b97 100644
--- a/src/rotation_generator.jl
+++ b/src/rotation_generator.jl
@@ -6,9 +6,6 @@ skew-symmetric real `N`×`N` matrices.
 """
 abstract type RotationGenerator{N,T} <: StaticMatrix{N,N,T} end
 
-Base.@pure StaticArrays.Size(::Type{RotationGenerator{N}}) where {N} = Size(N,N)
-Base.@pure StaticArrays.Size(::Type{RotationGenerator{N,T}}) where {N,T} = Size(N,N)
-Base.@pure StaticArrays.Size(::Type{R}) where {R<:RotationGenerator} = Size(supertype(R))
 Base.adjoint(r::RotationGenerator) = -r
 Base.transpose(r::RotationGenerator{N,T}) where {N,T<:Real} = -r
 Base.real(R::Type{<:RotationGenerator}) = R