diff --git a/producer/producer_nflegacy.go b/producer/producer_nflegacy.go
index 9c7e1dc..30d7659 100644
--- a/producer/producer_nflegacy.go
+++ b/producer/producer_nflegacy.go
@@ -14,10 +14,12 @@ func ConvertNetFlowLegacyRecord(baseTime uint32, uptime uint32, record netflowle
 
 	flowMessage.Type = flowmessage.FlowMessage_NETFLOW_V5
 
-	timeDiffFirst := (uptime - record.First) / 1000
-	timeDiffLast := (uptime - record.Last) / 1000
-	flowMessage.TimeFlowStart = uint64(baseTime - timeDiffFirst)
-	flowMessage.TimeFlowEnd = uint64(baseTime - timeDiffLast)
+	timeDiffFirst := (uptime - record.First)
+	timeDiffLast := (uptime - record.Last)
+	flowMessage.TimeFlowStart = uint64(baseTime - timeDiffFirst / 1000)
+	flowMessage.TimeFlowStartMs = uint64(baseTime)*1000 - uint64(timeDiffFirst)
+	flowMessage.TimeFlowEnd = uint64(baseTime - timeDiffLast / 1000)
+	flowMessage.TimeFlowEndMs = uint64(baseTime)*1000 - uint64(timeDiffLast)
 
 	v := make(net.IP, 4)
 	binary.BigEndian.PutUint32(v, record.NextHop)