diff --git a/src/main/java/org/traccar/helper/StringUtil.java b/src/main/java/org/traccar/helper/StringUtil.java
index 686e386a6..c366f6393 100644
--- a/src/main/java/org/traccar/helper/StringUtil.java
+++ b/src/main/java/org/traccar/helper/StringUtil.java
@@ -36,4 +36,12 @@ public final class StringUtil {
         return value.substring(start);
     }
 
+    public static String stripTrailing(char c, String value) {
+        int end = value.length();
+        while (end > 1 && value.charAt(end - 1) == c) {
+            end--;
+        }
+        return value.substring(0, end);
+    }
+
 }
diff --git a/src/main/java/org/traccar/protocol/CalAmpProtocolDecoder.java b/src/main/java/org/traccar/protocol/CalAmpProtocolDecoder.java
index 316c4a848..0d1dc3544 100644
--- a/src/main/java/org/traccar/protocol/CalAmpProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/CalAmpProtocolDecoder.java
@@ -24,6 +24,7 @@ import org.traccar.session.DeviceSession;
 import org.traccar.NetworkMessage;
 import org.traccar.Protocol;
 import org.traccar.helper.BitUtil;
+import org.traccar.helper.StringUtil;
 import org.traccar.helper.UnitsConverter;
 import org.traccar.model.Position;
 
@@ -166,7 +167,8 @@ public class CalAmpProtocolDecoder extends BaseProtocolDecoder {
             int content = buf.readUnsignedByte();
 
             if (BitUtil.check(content, 0)) {
-                String id = ByteBufUtil.hexDump(buf.readSlice(buf.readUnsignedByte())).replace("f", "");
+                String id = StringUtil.stripTrailing(
+                        'f', ByteBufUtil.hexDump(buf.readSlice(buf.readUnsignedByte())));
                 getDeviceSession(channel, remoteAddress, id);
             }
 
diff --git a/src/main/java/org/traccar/protocol/Gt06ProtocolDecoder.java b/src/main/java/org/traccar/protocol/Gt06ProtocolDecoder.java
index 164ddb933..85a89b478 100644
--- a/src/main/java/org/traccar/protocol/Gt06ProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/Gt06ProtocolDecoder.java
@@ -30,6 +30,7 @@ import org.traccar.helper.Checksum;
 import org.traccar.helper.DateBuilder;
 import org.traccar.helper.Parser;
 import org.traccar.helper.PatternBuilder;
+import org.traccar.helper.StringUtil;
 import org.traccar.helper.UnitsConverter;
 import org.traccar.model.CellTower;
 import org.traccar.model.Network;
@@ -1226,7 +1227,8 @@ public class Gt06ProtocolDecoder extends BaseProtocolDecoder {
 
                 buf.skipBytes(8); // imei
                 buf.skipBytes(8); // imsi
-                position.set(Position.KEY_ICCID, ByteBufUtil.hexDump(buf.readSlice(10)).replaceAll("f", ""));
+                position.set(Position.KEY_ICCID, StringUtil.stripTrailing(
+                        'f', ByteBufUtil.hexDump(buf.readSlice(10))));
                 return position;
 
             } else if (subType == 0x0b) {
diff --git a/src/main/java/org/traccar/protocol/Jt600ProtocolDecoder.java b/src/main/java/org/traccar/protocol/Jt600ProtocolDecoder.java
index 900a5edd2..0a1723dad 100644
--- a/src/main/java/org/traccar/protocol/Jt600ProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/Jt600ProtocolDecoder.java
@@ -29,6 +29,7 @@ import org.traccar.helper.BitUtil;
 import org.traccar.helper.DateBuilder;
 import org.traccar.helper.Parser;
 import org.traccar.helper.PatternBuilder;
+import org.traccar.helper.StringUtil;
 import org.traccar.helper.UnitsConverter;
 import org.traccar.model.CellTower;
 import org.traccar.model.Network;
@@ -122,7 +123,7 @@ public class Jt600ProtocolDecoder extends BaseProtocolDecoder {
 
         buf.readByte(); // header
 
-        String id = String.valueOf(Long.parseLong(ByteBufUtil.hexDump(buf.readSlice(5))));
+        String id = StringUtil.stripLeading('0', ByteBufUtil.hexDump(buf.readSlice(5)));
         DeviceSession deviceSession = getDeviceSession(channel, remoteAddress, id);
         if (deviceSession == null) {
             return null;
diff --git a/src/main/java/org/traccar/protocol/Jt808ProtocolDecoder.java b/src/main/java/org/traccar/protocol/Jt808ProtocolDecoder.java
index 93db3fab7..965c6e100 100644
--- a/src/main/java/org/traccar/protocol/Jt808ProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/Jt808ProtocolDecoder.java
@@ -1124,8 +1124,8 @@ public class Jt808ProtocolDecoder extends BaseProtocolDecoder {
                                     }
                                     break;
                                 case 0x00B2:
-                                    position.set(Position.KEY_ICCID, ByteBufUtil.hexDump(
-                                            buf.readSlice(10)).replaceAll("f", ""));
+                                    position.set(Position.KEY_ICCID, StringUtil.stripTrailing(
+                                            'f', ByteBufUtil.hexDump(buf.readSlice(10))));
                                     break;
                                 case 0x00B9:
                                     buf.readUnsignedByte(); // count