diff --git a/pySim/esim/saip/personalization.py b/pySim/esim/saip/personalization.py
index e1c1d57d..d227cff1 100644
--- a/pySim/esim/saip/personalization.py
+++ b/pySim/esim/saip/personalization.py
@@ -188,6 +188,9 @@ class ConfigurableParameter(abc.ABC, metaclass=ClassVarMeta):
             if cls.allow_chars is not None:
                 if any(c not in cls.allow_chars for c in val):
                     raise ValueError(f"invalid characters in input value {val!r}, valid chars are {cls.allow_chars}")
+        elif isinstance(val, io.BytesIO):
+            val = val.getvalue()
+
         if cls.allow_len is not None:
             l = cls.allow_len
             # cls.allow_len could be one int, or a tuple of ints. Wrap a single int also in a tuple.
diff --git a/tests/unittests/test_configurable_parameters.py b/tests/unittests/test_configurable_parameters.py
index d882af60..86ea199c 100755
--- a/tests/unittests/test_configurable_parameters.py
+++ b/tests/unittests/test_configurable_parameters.py
@@ -20,6 +20,7 @@
 import io
 import sys
 import unittest
+import io
 from importlib import resources
 from osmocom.utils import hexstr
 from pySim.esim.saip import ProfileElementSequence
@@ -143,6 +144,10 @@ class ConfigurableParameterTest(unittest.TestCase):
                       val=bytearray(b'\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16'),
                       expect_clean_val=b'\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16',
                       expect_val='01020304050607080910111213141516'),
+            Paramtest(param_cls=p13n.K,
+                      val=io.BytesIO(b'\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16'),
+                      expect_clean_val=b'\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16',
+                      expect_val='01020304050607080910111213141516'),
 
             Paramtest(param_cls=p13n.Opc,
                       val='01020304050607080910111213141516',
@@ -156,6 +161,10 @@ class ConfigurableParameterTest(unittest.TestCase):
                       val=bytearray(b'\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16'),
                       expect_clean_val=b'\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16',
                       expect_val='01020304050607080910111213141516'),
+            Paramtest(param_cls=p13n.Opc,
+                      val=io.BytesIO(b'\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16'),
+                      expect_clean_val=b'\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16',
+                      expect_val='01020304050607080910111213141516'),
             ]
 
         # SdKey classes don't make sense yet, will come in Ic92ddea6e1fad8167ea75baf78ffc3eb419838c4
diff --git a/tests/unittests/xo/test_configurable_parameters b/tests/unittests/xo/test_configurable_parameters
index 5fd2e7dd..5d99375f 100644
--- a/tests/unittests/xo/test_configurable_parameters
+++ b/tests/unittests/xo/test_configurable_parameters
@@ -71,6 +71,10 @@ ok: TS48v5_SAIP2.1A_NoBERTLV.der K(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10
 	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
 	read_back_val=	{'K': '01020304050607080910111213141516'}:{hexstr}
 
+ok: TS48v5_SAIP2.1A_NoBERTLV.der K(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':BytesIO)
+	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
+	read_back_val=	{'K': '01020304050607080910111213141516'}:{hexstr}
+
 ok: TS48v5_SAIP2.1A_NoBERTLV.der Opc(val=	'01020304050607080910111213141516':str)
 	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
 	read_back_val=	{'OPc': '01020304050607080910111213141516'}:{hexstr}
@@ -83,6 +87,10 @@ ok: TS48v5_SAIP2.1A_NoBERTLV.der Opc(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x
 	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
 	read_back_val=	{'OPc': '01020304050607080910111213141516'}:{hexstr}
 
+ok: TS48v5_SAIP2.1A_NoBERTLV.der Opc(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':BytesIO)
+	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
+	read_back_val=	{'OPc': '01020304050607080910111213141516'}:{hexstr}
+
 ok: TS48v5_SAIP2.3_BERTLV_SUCI.der Imsi(val=	'123456':str)
 	clean_val=	'123456':str
 	read_back_val=	{'IMSI': '123456', 'IMSI-ACC': '0040'}:{str, hexstr}
@@ -155,6 +163,10 @@ ok: TS48v5_SAIP2.3_BERTLV_SUCI.der K(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x
 	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
 	read_back_val=	{'K': '01020304050607080910111213141516'}:{hexstr}
 
+ok: TS48v5_SAIP2.3_BERTLV_SUCI.der K(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':BytesIO)
+	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
+	read_back_val=	{'K': '01020304050607080910111213141516'}:{hexstr}
+
 ok: TS48v5_SAIP2.3_BERTLV_SUCI.der Opc(val=	'01020304050607080910111213141516':str)
 	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
 	read_back_val=	{'OPc': '01020304050607080910111213141516'}:{hexstr}
@@ -167,6 +179,10 @@ ok: TS48v5_SAIP2.3_BERTLV_SUCI.der Opc(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t
 	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
 	read_back_val=	{'OPc': '01020304050607080910111213141516'}:{hexstr}
 
+ok: TS48v5_SAIP2.3_BERTLV_SUCI.der Opc(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':BytesIO)
+	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
+	read_back_val=	{'OPc': '01020304050607080910111213141516'}:{hexstr}
+
 ok: TS48v5_SAIP2.1B_NoBERTLV.der Imsi(val=	'123456':str)
 	clean_val=	'123456':str
 	read_back_val=	{'IMSI': '123456', 'IMSI-ACC': '0040'}:{str, hexstr}
@@ -239,6 +255,10 @@ ok: TS48v5_SAIP2.1B_NoBERTLV.der K(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10
 	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
 	read_back_val=	{'K': '01020304050607080910111213141516'}:{hexstr}
 
+ok: TS48v5_SAIP2.1B_NoBERTLV.der K(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':BytesIO)
+	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
+	read_back_val=	{'K': '01020304050607080910111213141516'}:{hexstr}
+
 ok: TS48v5_SAIP2.1B_NoBERTLV.der Opc(val=	'01020304050607080910111213141516':str)
 	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
 	read_back_val=	{'OPc': '01020304050607080910111213141516'}:{hexstr}
@@ -251,6 +271,10 @@ ok: TS48v5_SAIP2.1B_NoBERTLV.der Opc(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x
 	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
 	read_back_val=	{'OPc': '01020304050607080910111213141516'}:{hexstr}
 
+ok: TS48v5_SAIP2.1B_NoBERTLV.der Opc(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':BytesIO)
+	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
+	read_back_val=	{'OPc': '01020304050607080910111213141516'}:{hexstr}
+
 ok: TS48v5_SAIP2.3_NoBERTLV.der Imsi(val=	'123456':str)
 	clean_val=	'123456':str
 	read_back_val=	{'IMSI': '123456', 'IMSI-ACC': '0040'}:{str, hexstr}
@@ -323,6 +347,10 @@ ok: TS48v5_SAIP2.3_NoBERTLV.der K(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\
 	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
 	read_back_val=	{'K': '01020304050607080910111213141516'}:{hexstr}
 
+ok: TS48v5_SAIP2.3_NoBERTLV.der K(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':BytesIO)
+	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
+	read_back_val=	{'K': '01020304050607080910111213141516'}:{hexstr}
+
 ok: TS48v5_SAIP2.3_NoBERTLV.der Opc(val=	'01020304050607080910111213141516':str)
 	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
 	read_back_val=	{'OPc': '01020304050607080910111213141516'}:{hexstr}
@@ -334,3 +362,7 @@ ok: TS48v5_SAIP2.3_NoBERTLV.der Opc(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x1
 ok: TS48v5_SAIP2.3_NoBERTLV.der Opc(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytearray)
 	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
 	read_back_val=	{'OPc': '01020304050607080910111213141516'}:{hexstr}
+
+ok: TS48v5_SAIP2.3_NoBERTLV.der Opc(val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':BytesIO)
+	clean_val=	b'\x01\x02\x03\x04\x05\x06\x07\x08\t\x10\x11\x12\x13\x14\x15\x16':bytes
+	read_back_val=	{'OPc': '01020304050607080910111213141516'}:{hexstr}