diff --git a/sohstationviewer/model/reftek/reftek_data/reftek_helper.py b/sohstationviewer/model/reftek/reftek_data/reftek_helper.py
index 21976cbd68418ec14c7d4cec2ea1994ba4a37a89..e7b1ed24f706081f6655f67d9e428648ec4dad81 100644
--- a/sohstationviewer/model/reftek/reftek_data/reftek_helper.py
+++ b/sohstationviewer/model/reftek/reftek_data/reftek_helper.py
@@ -7,13 +7,11 @@ import numpy as np
 from sohstationviewer.model.mseed_data.record_reader_helper import Unpacker
 from sohstationviewer.model.reftek.reftek_data.packet import \
     eh_et_payload_end_in_packet
-from sohstationviewer.model.reftek.reftek_data.packet_readers import \
-    (
+from sohstationviewer.model.reftek.reftek_data.packet_readers import (
     read_dt_packet, read_eh_et_packet, read_soh_packet,
 )
 from sohstationviewer.model.reftek.reftek_data.packets import (
-    DTPacket,
-    EHETPacket, SOHPacket,
+    DTPacket, EHETPacket, SOHPacket,
 )
 from sohstationviewer.model.reftek.reftek_data.header import \
     get_rt130_packet_header