diff --git a/tc/obsw_pus_tc_base.py b/tc/obsw_pus_tc_base.py
index c5519f0978588b0c201b1fd98aeea4a23d6b790f..5ba96f7f77f256e6258ba74fcb04ad1263416f7c 100644
--- a/tc/obsw_pus_tc_base.py
+++ b/tc/obsw_pus_tc_base.py
@@ -53,7 +53,7 @@ class PusTelecommand:
         self.packet_id = (self.packet_id_bytes[0] << 8) | self.packet_id_bytes[1]
         self.ssc = ssc
         self.psc = (ssc & 0x3FFF) | (0xC0 << 8)
-        self.pus_version_and_ack_byte = 0b00011111
+        self.pus_version_and_ack_byte = 0b0001_1111
         self.service = service
         self.subservice = subservice
         self.source_id = source_id