diff --git a/ext/UnitfulExt.jl b/ext/UnitfulExt.jl
index 01139ac..929a92f 100644
--- a/ext/UnitfulExt.jl
+++ b/ext/UnitfulExt.jl
@@ -52,14 +52,14 @@ for PT in MonteCarloMeasurements.ParticleSymbols
             end
 
             function Base.$f(p::$PT{T,N}, y::Quantity{S,D,U}) where {S, D, U, T <: Number, N}
-                QT = Base.promote_op($op, T, typeof(y))
-                $PT{QT,N}($(op).(p.particles, y))
+                parts = $(op).(p.particles, y)
+                $PT{eltype(parts),N}(parts)
             end
 
             # Below is just the reverse signature of above
             function Base.$f(y::Quantity{S,D,U}, p::$PT{T,N}) where {S, D, U, T <: Number, N}
-                QT = Base.promote_op($op, typeof(y), T)
-                $PT{QT,N}($(op).(y, p.particles))
+                parts = $(op).(y, p.particles)
+                $PT{eltype(parts),N}(parts)
             end
 
             function Base.$f(p::$PT, y::Unitful.FreeUnits)
diff --git a/test/test_unitful.jl b/test/test_unitful.jl
index c52106d..3dd38d2 100644
--- a/test/test_unitful.jl
+++ b/test/test_unitful.jl
@@ -1,4 +1,4 @@
-using Unitful
+using Unitful, Test, MonteCarloMeasurements
 function unitful_testfunction(Vi)
     if Vi ≤ 0.0u"V"
         return 0.0u"V"
@@ -76,6 +76,10 @@ register_primitive(unitful_testfunction) # must be outside testset
         y = z * x
         @test y isa PT{<:Quantity}
         @test ustrip(u"cm", x*y) isa PT{Float64}
+
+        y = x * z
+        @test y isa PT{<:Quantity}
+        @test ustrip(u"cm", x*y) isa PT{Float64}
     end
 
 end