diff --git a/src/Base/Tools3D.cpp b/src/Base/Tools3D.cpp
index eb2a842a3c..af9694b251 100644
--- a/src/Base/Tools3D.cpp
+++ b/src/Base/Tools3D.cpp
@@ -77,13 +77,13 @@ bool Line3<float_type>::operator== (const Line3<float_type>& line) const
 }
 
 template <typename float_type>
-double Line3<float_type>::Length() const
+float_type Line3<float_type>::Length() const
 {
     return Base::Distance(p1, p2);
 }
 
 template <typename float_type>
-double Line3<float_type>::SqrLength() const
+float_type Line3<float_type>::SqrLength() const
 {
     return Base::DistanceP2(p1, p2);
 }
diff --git a/src/Base/Tools3D.h b/src/Base/Tools3D.h
index cc9a891d05..7c57d33be1 100644
--- a/src/Base/Tools3D.h
+++ b/src/Base/Tools3D.h
@@ -68,8 +68,8 @@ public:
     bool operator== (const Line3& line) const;
 
     // methods
-    double Length () const;
-    double SqrLength () const;
+    float_type Length () const;
+    float_type SqrLength () const;
     BoundBox3<float_type> CalcBoundBox() const;
     Vector3<float_type> GetBase() const;
     Vector3<float_type> GetDirection() const;