diff --git a/GUI/View/Instrument/InstrumentsTreeModel.cpp b/GUI/View/Instrument/InstrumentsTreeModel.cpp
index 68003f4b8713ede5c68d3c688328e061958792ac..3d80f88f4318abd0306ce2fc24f90ef06aeddbe6 100644
--- a/GUI/View/Instrument/InstrumentsTreeModel.cpp
+++ b/GUI/View/Instrument/InstrumentsTreeModel.cpp
@@ -19,10 +19,17 @@
 #include <QApplication>
 #include <QtGui>
 
+namespace {
+
+using IType = InstrumentsTreeModel::InstrumentType;
+const auto types = {IType::Gisas, IType::Offspec, IType::Specular, IType::Depthprobe};
+
+} // namespace
+
+
 InstrumentsTreeModel::InstrumentsTreeModel(QObject* parent, InstrumentModel* model)
     : QAbstractItemModel(parent)
     , m_model(model)
-    , m_visibleTypes(All)
     , m_namesAreEditable(false)
     , m_enableEmptyHeadlines(true)
 {
@@ -43,24 +50,6 @@ void InstrumentsTreeModel::clear()
     endResetModel();
 }
 
-QList<InstrumentsTreeModel::InstrumentType> InstrumentsTreeModel::visibleTypes() const
-{
-    QList<InstrumentsTreeModel::InstrumentType> result;
-
-    const auto forType = [&](InstrumentType type) {
-        if (m_visibleTypes.testFlag(type)
-            && (m_enableEmptyHeadlines || !instrumentItemsOfType(type).isEmpty()))
-            result << type;
-    };
-
-    forType(Gisas);
-    forType(Offspec);
-    forType(Specular);
-    forType(Depthprobe);
-
-    return result;
-}
-
 QVector<InstrumentItem*> InstrumentsTreeModel::instrumentItemsOfType(InstrumentType type) const
 {
     switch (type) {
@@ -88,7 +77,7 @@ QVector<InstrumentItem*> InstrumentsTreeModel::instrumentItemsOfType(InstrumentT
 QModelIndex InstrumentsTreeModel::indexOfHeadline(InstrumentType type) const
 {
     int row = 0;
-    for (auto t : visibleTypes()) {
+    for (auto t : ::types) {
         if (t == type)
             return createIndex(row, 0, nullptr);
         row++;
@@ -105,7 +94,7 @@ QModelIndex InstrumentsTreeModel::index(int row, int column, const QModelIndex&
     if (!parent.isValid())
         return createIndex(row, column, nullptr);
 
-    for (auto type : visibleTypes())
+    for (auto type : ::types)
         if (parent == indexOfHeadline(type))
             return createIndex(row, column, instrumentItemsOfType(type)[row]);
 
@@ -121,7 +110,7 @@ QModelIndex InstrumentsTreeModel::parent(const QModelIndex& index) const
         return QModelIndex();
 
     auto* item = itemForIndex(index);
-    for (auto type : visibleTypes())
+    for (auto type : ::types)
         if (instrumentItemsOfType(type).contains(item))
             return indexOfHeadline(type);
 
@@ -136,10 +125,10 @@ int InstrumentsTreeModel::columnCount(const QModelIndex& /*parent*/) const
 int InstrumentsTreeModel::rowCount(const QModelIndex& parent) const
 {
     if (!parent.isValid())
-        return visibleTypes().size();
+        return ::types.size();
 
     // parent is a headline
-    for (auto type : visibleTypes())
+    for (auto type : ::types)
         if (parent == indexOfHeadline(type))
             return instrumentItemsOfType(type).size();
 
@@ -270,7 +259,7 @@ QModelIndex InstrumentsTreeModel::indexForItem(InstrumentItem* item) const
     if (item == nullptr)
         return QModelIndex();
 
-    for (auto type : visibleTypes())
+    for (auto type : ::types)
         if (auto row = instrumentItemsOfType(type).indexOf(item); row >= 0)
             return createIndex(row, 0, item);
 
diff --git a/GUI/View/Instrument/InstrumentsTreeModel.h b/GUI/View/Instrument/InstrumentsTreeModel.h
index a5d6bd26a91aa0c18114e7a389071bc13c74cd49..3ba2e85a5635ed27e8e94339cae2d2c1dbeddbf1 100644
--- a/GUI/View/Instrument/InstrumentsTreeModel.h
+++ b/GUI/View/Instrument/InstrumentsTreeModel.h
@@ -60,12 +60,10 @@ public:
 
 private:
     void clear();
-    QList<InstrumentType> visibleTypes() const;
     QVector<InstrumentItem*> instrumentItemsOfType(InstrumentType type) const;
 
 private:
     InstrumentModel* m_model = nullptr;
-    VisibleInstrumentTypes m_visibleTypes;
     bool m_namesAreEditable;
     bool m_enableEmptyHeadlines;
 };