diff --git a/REMAN/NKC.Data/DbModels/MaterialModel.cs b/REMAN/NKC.Data/DbModels/MaterialModel.cs
index fef5efb..e1a64e4 100644
--- a/REMAN/NKC.Data/DbModels/MaterialModel.cs
+++ b/REMAN/NKC.Data/DbModels/MaterialModel.cs
@@ -28,6 +28,6 @@ namespace NKC.Data.DbModels
         }
 
 
-        public virtual ICollection<RemnantsModel> RemnantNav { get; set; }
+        public virtual ICollection<RemnantsModel>? RemnantNav { get; set; }
     }
 }
diff --git a/REMAN/NKC.Data/DbModels/MovMagModel.cs b/REMAN/NKC.Data/DbModels/MovMagModel.cs
index 3a61dd8..54037aa 100644
--- a/REMAN/NKC.Data/DbModels/MovMagModel.cs
+++ b/REMAN/NKC.Data/DbModels/MovMagModel.cs
@@ -42,7 +42,7 @@ namespace NKC.Data.DbModels
         /// Navigation property to Remnant
         /// </summary>
         [ForeignKey("RemnID")]
-        public virtual RemnantsModel RemnantNav { get; set; }
+        public virtual RemnantsModel? RemnantNav { get; set; }
 
     }
 }
diff --git a/REMAN/NKC.Data/DbModels/RemnantsModel.cs b/REMAN/NKC.Data/DbModels/RemnantsModel.cs
index 71e4c38..072948c 100644
--- a/REMAN/NKC.Data/DbModels/RemnantsModel.cs
+++ b/REMAN/NKC.Data/DbModels/RemnantsModel.cs
@@ -31,7 +31,7 @@ namespace NKC.Data.DbModels
         /// Qty available on wharehouse
         /// </summary>
         public int QtyAvail { get; set; } = 0;
-        
+
         /// <summary>
         /// DateTime last modification
         /// </summary>
@@ -45,12 +45,12 @@ namespace NKC.Data.DbModels
         /// <summary>
         /// Remnant's Width
         /// </summary>
-        public decimal WMm { get; set; }=0;
-        
+        public decimal WMm { get; set; } = 0;
+
         /// <summary>
         /// Remnant's Thikness
         /// </summary>
-        public decimal TMm { get; set; }=0;
+        public decimal TMm { get; set; } = 0;
 
         [NotMapped]
         public decimal LIn
@@ -84,14 +84,22 @@ namespace NKC.Data.DbModels
         [NotMapped]
         public string RemDtmx
         {
-            get => $"MT{MaterialNav.MatExtCode:00000000}-{LMm*1000:00000000}";
+            get
+            {
+                string answ = $"MT99999999-{LMm * 1000:00000000}";
+                if (MaterialNav != null)
+                {
+                    answ = $"MT{MaterialNav.MatExtCode:00000000}-{LMm * 1000:00000000}";
+                }
+                return answ;
+            }
         }
 
         /// <summary>
         /// Navigation property to Material
         /// </summary>
         [ForeignKey("MatID")]
-        public virtual MaterialModel MaterialNav { get; set; }
+        public virtual MaterialModel? MaterialNav { get; set; }
 
     }
 }