diff --git a/RhSolutions.Parsers.Tests/RautitanFittingsTests.cs b/RhSolutions.Parsers.Tests/RautitanFittingsTests.cs
index e20fcda..e9a9c89 100644
--- a/RhSolutions.Parsers.Tests/RautitanFittingsTests.cs
+++ b/RhSolutions.Parsers.Tests/RautitanFittingsTests.cs
@@ -34,6 +34,7 @@ public class RautitanFittingsTests : ProductParsersTests
 		=> Invoke(productType: "Муфта соединительная", query, modified);
 		
 	[TestCase("Переходник с внутренней резьбой 16xG 3/4\" для труб из сшитого полиэтилена аксиальный", "Переходник с внутренней резьбой -угольник-переходник 16 3/4")]
+	[TestCase("Переходник на внутреннюю резьбу 20", "Переходник с внутренней резьбой -угольник-переходник 20 1/2")]
 	public void AdapterInternalTest(string query, string modified)
 		=> Invoke(productType: "Переходник на внутреннюю резьбу", query, modified);
 	
diff --git a/RhSolutions.Parsers/DrinkingWaterHeatingFittings/Adapter.cs b/RhSolutions.Parsers/DrinkingWaterHeatingFittings/Adapter.cs
index 59da412..8ef4f33 100644
--- a/RhSolutions.Parsers/DrinkingWaterHeatingFittings/Adapter.cs
+++ b/RhSolutions.Parsers/DrinkingWaterHeatingFittings/Adapter.cs
@@ -4,6 +4,16 @@ namespace RhSolutions.Parsers.Fittings;
 
 public abstract class Adapter : DrinkingWaterHeatingFitting
 {
+	protected Dictionary<string, string> _defaultThreads = new()
+	{
+		["16"] = "1/2",
+		["20"] = "1/2",
+		["25"] = "3/4",
+		["32"] = "1",
+		["40"] = "1 1/4",
+		["50"] = "1 1/2",
+		["63"] = "2"
+	};
 	public override bool TryParse(string input, out string output)
 	{		
 		output = string.Empty;
@@ -13,11 +23,16 @@ public abstract class Adapter : DrinkingWaterHeatingFitting
 			return false;
 		}
 		Match thread = _thread.Match(input);
+		string threadValue;
 		if (!thread.Success)
 		{
-			return false;
+			threadValue = _defaultThreads[diameter.Groups["Diameter"].Value];
 		}
-		output = $"{_title} {diameter.Groups["Diameter"]} {thread.Groups["Thread"]}";
+		else
+		{
+			threadValue = thread.Groups["Thread"].Value;
+		}
+		output = $"{_title} {diameter.Groups["Diameter"]} {threadValue}";
 		return true;
 	}
 }