diff --git a/src/AddIn/EventsUtil.cs b/src/AddIn/EventsUtil.cs
index 102e12e..bc8d1d3 100644
--- a/src/AddIn/EventsUtil.cs
+++ b/src/AddIn/EventsUtil.cs
@@ -4,7 +4,7 @@ namespace RehauSku
 {
     internal static class EventsUtil
     {
-        private static Application Excel = AddIn.Excel;
+        private static readonly Application Excel = AddIn.Excel;
 
         public static void Initialize()
         {
diff --git a/src/AddIn/WorksheetExtensions.cs b/src/AddIn/WorksheetExtensions.cs
index cffa55c..7880b66 100644
--- a/src/AddIn/WorksheetExtensions.cs
+++ b/src/AddIn/WorksheetExtensions.cs
@@ -1,15 +1,11 @@
 using Microsoft.Office.Interop.Excel;
+using RehauSku.PriceListTools;
 using System.Linq;
 
 namespace RehauSku
 {
     public static class WorksheetExtensions
     {
-        private static string amountHeader = "Кол-во";
-        private static string skuHeader = "Актуальный материал";
-        private static string groupHeader = "Программа";
-        private static string nameHeader = "Наименование";
-
         public static bool IsRehauSource(this Worksheet worksheet)
         {
             Range amountCell;
@@ -19,10 +15,10 @@ namespace RehauSku
 
             Range[] cells = new[]
             {
-                amountCell = worksheet.Cells.Find(amountHeader),
-                skuCell = worksheet.Cells.Find(skuHeader),
-                groupCell = worksheet.Cells.Find(groupHeader),
-                nameCell = worksheet.Cells.Find(nameHeader)
+                amountCell = worksheet.Cells.Find(PriceListHeaders.Amount),
+                skuCell = worksheet.Cells.Find(PriceListHeaders.Sku),
+                groupCell = worksheet.Cells.Find(PriceListHeaders.Group),
+                nameCell = worksheet.Cells.Find(PriceListHeaders.Name)
             };
 
             return cells.All(x => x != null);
diff --git a/src/Interface/ProgressBar.cs b/src/Interface/ProgressBar.cs
index 2e68e8b..416c7d6 100644
--- a/src/Interface/ProgressBar.cs
+++ b/src/Interface/ProgressBar.cs
@@ -19,7 +19,7 @@
 
             if (percent < 100)
             {
-                Excel.StatusBar = $"{Message} Выполнено {percent.ToString("#.#")} %";
+                Excel.StatusBar = $"{Message} Выполнено {percent:#.#} %";
             }
 
             else
diff --git a/src/PriceListTools/AbstractPriceList.cs b/src/PriceListTools/AbstractPriceList.cs
index 06427a0..2f89a85 100644
--- a/src/PriceListTools/AbstractPriceList.cs
+++ b/src/PriceListTools/AbstractPriceList.cs
@@ -4,15 +4,10 @@ namespace RehauSku.PriceListTools
 {
     internal abstract class AbstractPriceList
     {
-        protected const string amountHeader = "Кол-во";
-        protected const string skuHeader = "Актуальный материал";
-        protected const string groupHeader = "Программа";
-        protected const string nameHeader = "Наименование";
-
-        public Range amountCell { get; protected set; }
-        public Range skuCell { get; protected set; }
-        public Range groupCell { get; protected set; }
-        public Range nameCell { get; protected set; }
+        public Range AmountCell { get; protected set; }
+        public Range SkuCell { get; protected set; }
+        public Range GroupCell { get; protected set; }
+        public Range NameCell { get; protected set; }
 
         public Worksheet Sheet { get; protected set; }
         public string Name { get; protected set; }
diff --git a/src/PriceListTools/AbstractTool.cs b/src/PriceListTools/AbstractTool.cs
index c43d06c..256be06 100644
--- a/src/PriceListTools/AbstractTool.cs
+++ b/src/PriceListTools/AbstractTool.cs
@@ -45,7 +45,7 @@ namespace RehauSku.PriceListTools
 
         protected void FillPositionAmountToColumns(KeyValuePair<Position, double> positionAmount, params int[] columns)
         {
-            int? row = GetPositionRow(TargetFile.skuCell.EntireColumn, positionAmount.Key.Sku, positionAmount.Key.Group);
+            int? row = GetPositionRow(TargetFile.SkuCell.EntireColumn, positionAmount.Key.Sku, positionAmount.Key.Group);
 
             if (row != null)
             {
@@ -59,9 +59,9 @@ namespace RehauSku.PriceListTools
                 return;
             }
 
-            if (TargetFile.oldSkuCell != null)
+            if (TargetFile.OldSkuCell != null)
             {
-                row = GetPositionRow(TargetFile.oldSkuCell.EntireColumn, positionAmount.Key.Sku, positionAmount.Key.Group);
+                row = GetPositionRow(TargetFile.OldSkuCell.EntireColumn, positionAmount.Key.Sku, positionAmount.Key.Group);
 
                 if (row != null)
                 {
@@ -77,7 +77,7 @@ namespace RehauSku.PriceListTools
             }
 
             string sku = positionAmount.Key.Sku.Substring(1, 6);
-            row = GetPositionRow(TargetFile.skuCell.EntireColumn, sku, positionAmount.Key.Group);
+            row = GetPositionRow(TargetFile.SkuCell.EntireColumn, sku, positionAmount.Key.Group);
 
             if (row != null)
             {
@@ -97,7 +97,7 @@ namespace RehauSku.PriceListTools
 
         protected void FillMissing(KeyValuePair<Position, double> positionAmount, params int[] columns)
         {
-            int row = TargetFile.Sheet.Cells[TargetFile.Sheet.Rows.Count, TargetFile.skuCell.Column]
+            int row = TargetFile.Sheet.Cells[TargetFile.Sheet.Rows.Count, TargetFile.SkuCell.Column]
                 .End[XlDirection.xlUp]
                 .Row + 1;
 
@@ -111,18 +111,18 @@ namespace RehauSku.PriceListTools
             previous.Copy(current);
             current.ClearContents();
 
-            TargetFile.Sheet.Cells[row, TargetFile.groupCell.Column].Value2 = positionAmount.Key.Group;
-            TargetFile.Sheet.Cells[row, TargetFile.nameCell.Column].Value2 = positionAmount.Key.Name;
+            TargetFile.Sheet.Cells[row, TargetFile.GroupCell.Column].Value2 = positionAmount.Key.Group;
+            TargetFile.Sheet.Cells[row, TargetFile.NameCell.Column].Value2 = positionAmount.Key.Name;
 
-            if (TargetFile.oldSkuCell != null)
+            if (TargetFile.OldSkuCell != null)
             {
-                TargetFile.Sheet.Cells[row, TargetFile.skuCell.Column].Value2 = "Не найден";
-                TargetFile.Sheet.Cells[row, TargetFile.oldSkuCell.Column].Value2 = positionAmount.Key.Sku;
+                TargetFile.Sheet.Cells[row, TargetFile.SkuCell.Column].Value2 = "Не найден";
+                TargetFile.Sheet.Cells[row, TargetFile.OldSkuCell.Column].Value2 = positionAmount.Key.Sku;
             }
 
             else
             {
-                TargetFile.Sheet.Cells[row, TargetFile.skuCell.Column].Value2 = positionAmount.Key.Sku;
+                TargetFile.Sheet.Cells[row, TargetFile.SkuCell.Column].Value2 = positionAmount.Key.Sku;
             }
 
             foreach (int column in columns)
@@ -146,7 +146,7 @@ namespace RehauSku.PriceListTools
 
             while (true)
             {
-                foundGroupValue = TargetFile.Sheet.Cells[found.Row, TargetFile.groupCell.Column].Value2.ToString();
+                foundGroupValue = TargetFile.Sheet.Cells[found.Row, TargetFile.GroupCell.Column].Value2.ToString();
 
                 if (string.IsNullOrEmpty(group) || group.Equals(foundGroupValue))
                 {
@@ -167,7 +167,7 @@ namespace RehauSku.PriceListTools
             AutoFilter filter = TargetFile.Sheet.AutoFilter;
             int startColumn = filter.Range.Column;
 
-            filter.Range.AutoFilter(TargetFile.amountCell.Column - startColumn + 1, "<>");
+            filter.Range.AutoFilter(TargetFile.AmountCell.Column - startColumn + 1, "<>");
             TargetFile.Sheet.Range["A1"].Activate();
         }
     }
diff --git a/src/PriceListTools/CombineTool.cs b/src/PriceListTools/CombineTool.cs
index e3cb83e..eddf9e7 100644
--- a/src/PriceListTools/CombineTool.cs
+++ b/src/PriceListTools/CombineTool.cs
@@ -33,17 +33,17 @@ namespace RehauSku.PriceListTools
 
             foreach (SourcePriceList source in SourceFiles)
             {
-                TargetFile.Sheet.Columns[TargetFile.amountCell.Column]
+                TargetFile.Sheet.Columns[TargetFile.AmountCell.Column]
                     .EntireColumn
                     .Insert(XlInsertShiftDirection.xlShiftToRight, XlInsertFormatOrigin.xlFormatFromRightOrBelow);
 
-                Range newColumnHeader = TargetFile.Sheet.Cells[TargetFile.amountCell.Row, TargetFile.amountCell.Column - 1];
+                Range newColumnHeader = TargetFile.Sheet.Cells[TargetFile.AmountCell.Row, TargetFile.AmountCell.Column - 1];
                 newColumnHeader.Value2 = $"{source.Name}";
                 newColumnHeader.WrapText = true;
 
                 foreach (var kvp in source.PositionAmount)
                 {
-                    FillPositionAmountToColumns(kvp, TargetFile.amountCell.Column - 1, TargetFile.amountCell.Column);
+                    FillPositionAmountToColumns(kvp, TargetFile.AmountCell.Column - 1, TargetFile.AmountCell.Column);
                     ProgressBar.Update();
                 }
             }
diff --git a/src/PriceListTools/ConvertTool.cs b/src/PriceListTools/ConvertTool.cs
index abf7e39..1bb02f4 100644
--- a/src/PriceListTools/ConvertTool.cs
+++ b/src/PriceListTools/ConvertTool.cs
@@ -18,7 +18,7 @@ namespace RehauSku.PriceListTools
 
             foreach (var kvp in Current.PositionAmount)
             {
-                FillPositionAmountToColumns(kvp, TargetFile.amountCell.Column);
+                FillPositionAmountToColumns(kvp, TargetFile.AmountCell.Column);
                 ProgressBar.Update();
             }
 
diff --git a/src/PriceListTools/ExportTool.cs b/src/PriceListTools/ExportTool.cs
index acc6515..603de8b 100644
--- a/src/PriceListTools/ExportTool.cs
+++ b/src/PriceListTools/ExportTool.cs
@@ -8,7 +8,7 @@ namespace RehauSku.PriceListTools
     internal class ExportTool : AbstractTool
     {
         private Dictionary<Position, double> PositionAmount;
-        private Range Selection;
+        private readonly Range Selection;
 
         public ExportTool()
         {
@@ -28,7 +28,7 @@ namespace RehauSku.PriceListTools
             
             foreach (var kvp in PositionAmount)
             {
-                FillPositionAmountToColumns(kvp, TargetFile.amountCell.Column);
+                FillPositionAmountToColumns(kvp, TargetFile.AmountCell.Column);
                 ProgressBar.Update();
             }
 
diff --git a/src/PriceListTools/MergeTool.cs b/src/PriceListTools/MergeTool.cs
index 77732bf..179fb81 100644
--- a/src/PriceListTools/MergeTool.cs
+++ b/src/PriceListTools/MergeTool.cs
@@ -33,7 +33,7 @@ namespace RehauSku.PriceListTools
             {
                 foreach (var kvp in source.PositionAmount)
                 {
-                    FillPositionAmountToColumns(kvp, TargetFile.amountCell.Column);
+                    FillPositionAmountToColumns(kvp, TargetFile.AmountCell.Column);
                     ProgressBar.Update();
                 }
             }
diff --git a/src/PriceListTools/PriceListHeaders.cs b/src/PriceListTools/PriceListHeaders.cs
new file mode 100644
index 0000000..74c7870
--- /dev/null
+++ b/src/PriceListTools/PriceListHeaders.cs
@@ -0,0 +1,11 @@
+namespace RehauSku.PriceListTools
+{
+    internal static class PriceListHeaders
+    {
+        public static readonly string Amount = "Кол-во";
+        public static readonly string OldSku = "Прежний материал";
+        public static readonly string Sku = "Актуальный материал";
+        public static readonly string Group = "Программа";
+        public static readonly string Name = "Наименование";
+    }
+}
\ No newline at end of file
diff --git a/src/PriceListTools/SourcePriceList.cs b/src/PriceListTools/SourcePriceList.cs
index 01637f8..d03d776 100644
--- a/src/PriceListTools/SourcePriceList.cs
+++ b/src/PriceListTools/SourcePriceList.cs
@@ -7,7 +7,6 @@ using RehauSku.Interface;
 
 namespace RehauSku.PriceListTools
 {
-
     internal class SourcePriceList : AbstractPriceList
     {
         public Dictionary<Position, double> PositionAmount { get; private set; }
@@ -24,10 +23,10 @@ namespace RehauSku.PriceListTools
 
             Range[] cells = new[]
             {
-                amountCell = Sheet.Cells.Find(amountHeader),
-                skuCell = Sheet.Cells.Find(skuHeader),
-                groupCell = Sheet.Cells.Find(groupHeader),
-                nameCell = Sheet.Cells.Find(nameHeader)
+                AmountCell = Sheet.Cells.Find(PriceListHeaders.Amount),
+                SkuCell = Sheet.Cells.Find(PriceListHeaders.Sku),
+                GroupCell = Sheet.Cells.Find(PriceListHeaders.Group),
+                NameCell = Sheet.Cells.Find(PriceListHeaders.Name)
             };
 
             if (cells.Any(x => x == null))
@@ -76,15 +75,15 @@ namespace RehauSku.PriceListTools
         {
             PositionAmount = new Dictionary<Position, double>();
 
-            for (int row = amountCell.Row + 1; row <= Sheet.Cells[Sheet.Rows.Count, amountCell.Column].End[XlDirection.xlUp].Row; row++)
+            for (int row = AmountCell.Row + 1; row <= Sheet.Cells[Sheet.Rows.Count, AmountCell.Column].End[XlDirection.xlUp].Row; row++)
             {
-                object amount = Sheet.Cells[row, amountCell.Column].Value2;
+                object amount = Sheet.Cells[row, AmountCell.Column].Value2;
 
                 if (amount != null && (double)amount != 0)
                 {
-                    object group = Sheet.Cells[row, groupCell.Column].Value2;
-                    object name = Sheet.Cells[row, nameCell.Column].Value2;
-                    object sku = Sheet.Cells[row, skuCell.Column].Value2;
+                    object group = Sheet.Cells[row, GroupCell.Column].Value2;
+                    object name = Sheet.Cells[row, NameCell.Column].Value2;
+                    object sku = Sheet.Cells[row, SkuCell.Column].Value2;
 
                     if (group == null || name == null || sku == null)
                         continue;
diff --git a/src/PriceListTools/TargetPriceList.cs b/src/PriceListTools/TargetPriceList.cs
index 5fb2bf9..2f23168 100644
--- a/src/PriceListTools/TargetPriceList.cs
+++ b/src/PriceListTools/TargetPriceList.cs
@@ -6,8 +6,7 @@ namespace RehauSku.PriceListTools
 {
     internal class TargetPriceList : AbstractPriceList
     {
-        private const string oldSkuHeader = "Прежний материал";
-        public Range oldSkuCell { get; private set; }
+        public Range OldSkuCell { get; private set; }
 
         public TargetPriceList(Workbook workbook)
         {
@@ -22,13 +21,13 @@ namespace RehauSku.PriceListTools
 
             Range[] cells = new[]
             {
-                amountCell = Sheet.Cells.Find(amountHeader),
-                skuCell = Sheet.Cells.Find(skuHeader),
-                groupCell = Sheet.Cells.Find(groupHeader),
-                nameCell = Sheet.Cells.Find(nameHeader)
+                AmountCell = Sheet.Cells.Find(PriceListHeaders.Amount),
+                SkuCell = Sheet.Cells.Find(PriceListHeaders.Sku),
+                GroupCell = Sheet.Cells.Find(PriceListHeaders.Group),
+                NameCell = Sheet.Cells.Find(PriceListHeaders.Name)
             };
 
-            oldSkuCell = Sheet.Cells.Find(oldSkuHeader);
+            OldSkuCell = Sheet.Cells.Find(PriceListHeaders.OldSku);
 
             if (cells.Any(x => x == null))
             {
diff --git a/src/RehauSku.Assist.csproj b/src/RehauSku.Assist.csproj
index 76bd243..8a2990b 100644
--- a/src/RehauSku.Assist.csproj
+++ b/src/RehauSku.Assist.csproj
@@ -131,6 +131,7 @@
     <Compile Include="PriceListTools\AbstractTool.cs" />
     <Compile Include="PriceListTools\MergeTool.cs" />
     <Compile Include="PriceListTools\AbstractPriceList.cs" />
+    <Compile Include="PriceListTools\PriceListHeaders.cs" />
     <Compile Include="PriceListTools\SourcePriceList.cs" />
     <Compile Include="PriceListTools\TargetPriceList.cs" />
     <Compile Include="Interface\RibbonController.cs" />