diff --git a/tests/device_tests/test_msg_signtx_bcc.py b/tests/device_tests/test_msg_signtx_bcc.py
index 44967b4..8ce2394 100644
--- a/tests/device_tests/test_msg_signtx_bcc.py
+++ b/tests/device_tests/test_msg_signtx_bcc.py
@@ -129,7 +129,7 @@ class TestMsgSigntxSegwit(common.TrezorTest):
             msg.inputs[0].amount = 123400000
             run_attack = False
             return msg
-        
+
         with self.client:
             self.client.set_expected_responses([
                 proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0)),
@@ -192,7 +192,7 @@ class TestMsgSigntxSegwit(common.TrezorTest):
 
             msg.inputs[0].address_n[2] = 1 + 0x80000000
             return msg
-        
+
         with self.client:
             self.client.set_expected_responses([
                 proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0)),
diff --git a/tests/device_tests/test_msg_signtx_zcash.py b/tests/device_tests/test_msg_signtx_zcash.py
index 142fc6b..152ba7d 100644
--- a/tests/device_tests/test_msg_signtx_zcash.py
+++ b/tests/device_tests/test_msg_signtx_zcash.py
@@ -25,6 +25,9 @@ import trezorlib.types_pb2 as proto_types
 from trezorlib.tx_api import TxApiZcashTestnet
 
 
+TXHASH_93373e = binascii.unhexlify('93373e63cc626c4a7d049ad775d6511bb5eba985f142db660c9b9f955c722f5c')
+
+
 class TestMsgSigntx(common.TrezorTest):
 
     def test_one_one_fee(self):
@@ -36,7 +39,7 @@ class TestMsgSigntx(common.TrezorTest):
         inp1 = proto_types.TxInputType(
             address_n=[2147483692, 2147483649, 2147483648, 0, 0],  # tmQoJ3PTXgQLaRRZZYT6xk8XtjRbr2kCqwu
             # amount=123456700,
-            prev_hash=binascii.unhexlify('93373e63cc626c4a7d049ad775d6511bb5eba985f142db660c9b9f955c722f5c'),
+            prev_hash=TXHASH_93373e,
             prev_index=0,
         )
 
@@ -50,12 +53,12 @@ class TestMsgSigntx(common.TrezorTest):
             self.client.set_tx_api(TxApiZcashTestnet)
             self.client.set_expected_responses([
                 proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0)),
-                proto.TxRequest(request_type=proto_types.TXMETA, details=proto_types.TxRequestDetailsType(tx_hash=binascii.unhexlify("93373e63cc626c4a7d049ad775d6511bb5eba985f142db660c9b9f955c722f5c"))),
-                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=binascii.unhexlify("93373e63cc626c4a7d049ad775d6511bb5eba985f142db660c9b9f955c722f5c"))),
-                proto.TxRequest(request_type=proto_types.TXEXTRADATA, details=proto_types.TxRequestDetailsType(tx_hash=binascii.unhexlify("93373e63cc626c4a7d049ad775d6511bb5eba985f142db660c9b9f955c722f5c"), extra_data_offset=0, extra_data_len=1024)),
-                proto.TxRequest(request_type=proto_types.TXEXTRADATA, details=proto_types.TxRequestDetailsType(tx_hash=binascii.unhexlify("93373e63cc626c4a7d049ad775d6511bb5eba985f142db660c9b9f955c722f5c"), extra_data_offset=1024, extra_data_len=1024)),
-                proto.TxRequest(request_type=proto_types.TXEXTRADATA, details=proto_types.TxRequestDetailsType(tx_hash=binascii.unhexlify("93373e63cc626c4a7d049ad775d6511bb5eba985f142db660c9b9f955c722f5c"), extra_data_offset=2048, extra_data_len=1024)),
-                proto.TxRequest(request_type=proto_types.TXEXTRADATA, details=proto_types.TxRequestDetailsType(tx_hash=binascii.unhexlify("93373e63cc626c4a7d049ad775d6511bb5eba985f142db660c9b9f955c722f5c"), extra_data_offset=3072, extra_data_len=629)),
+                proto.TxRequest(request_type=proto_types.TXMETA, details=proto_types.TxRequestDetailsType(tx_hash=TXHASH_93373e)),
+                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=TXHASH_93373e)),
+                proto.TxRequest(request_type=proto_types.TXEXTRADATA, details=proto_types.TxRequestDetailsType(tx_hash=TXHASH_93373e, extra_data_offset=0, extra_data_len=1024)),
+                proto.TxRequest(request_type=proto_types.TXEXTRADATA, details=proto_types.TxRequestDetailsType(tx_hash=TXHASH_93373e, extra_data_offset=1024, extra_data_len=1024)),
+                proto.TxRequest(request_type=proto_types.TXEXTRADATA, details=proto_types.TxRequestDetailsType(tx_hash=TXHASH_93373e, extra_data_offset=2048, extra_data_len=1024)),
+                proto.TxRequest(request_type=proto_types.TXEXTRADATA, details=proto_types.TxRequestDetailsType(tx_hash=TXHASH_93373e, extra_data_offset=3072, extra_data_len=629)),
                 proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0)),
                 proto.ButtonRequest(code=proto_types.ButtonRequest_ConfirmOutput),
                 proto.ButtonRequest(code=proto_types.ButtonRequest_SignTx),
diff --git a/tests/device_tests/test_multisig.py b/tests/device_tests/test_multisig.py
index ef93b64..4a5d3b0 100644
--- a/tests/device_tests/test_multisig.py
+++ b/tests/device_tests/test_multisig.py
@@ -27,6 +27,10 @@ import trezorlib.ckd_public as bip32
 import trezorlib.types_pb2 as proto_types
 from trezorlib.client import CallException
 
+
+TXHASH_c6091a = binascii.unhexlify('c6091adf4c0c23982a35899a6e58ae11e703eacd7954f588ed4b9cdefc4dba52')
+
+
 # Multisig howto:
 #
 # https://sx.dyne.org/multisig.html
@@ -74,7 +78,7 @@ class TestMultisig(common.TrezorTest):
         # Let's go to sign with key 1
         inp1 = proto_types.TxInputType(
             address_n=[1],
-            prev_hash=binascii.unhexlify('c6091adf4c0c23982a35899a6e58ae11e703eacd7954f588ed4b9cdefc4dba52'),
+            prev_hash=TXHASH_c6091a,
             prev_index=1,
             script_type=proto_types.SPENDMULTISIG,
             multisig=multisig,
@@ -89,10 +93,10 @@ class TestMultisig(common.TrezorTest):
         with self.client:
             self.client.set_expected_responses([
                 proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0)),
-                proto.TxRequest(request_type=proto_types.TXMETA, details=proto_types.TxRequestDetailsType(tx_hash=binascii.unhexlify("c6091adf4c0c23982a35899a6e58ae11e703eacd7954f588ed4b9cdefc4dba52"))),
-                proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=binascii.unhexlify("c6091adf4c0c23982a35899a6e58ae11e703eacd7954f588ed4b9cdefc4dba52"))),
-                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=binascii.unhexlify("c6091adf4c0c23982a35899a6e58ae11e703eacd7954f588ed4b9cdefc4dba52"))),
-                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=1, tx_hash=binascii.unhexlify("c6091adf4c0c23982a35899a6e58ae11e703eacd7954f588ed4b9cdefc4dba52"))),
+                proto.TxRequest(request_type=proto_types.TXMETA, details=proto_types.TxRequestDetailsType(tx_hash=TXHASH_c6091a)),
+                proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=TXHASH_c6091a)),
+                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=TXHASH_c6091a)),
+                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=1, tx_hash=TXHASH_c6091a)),
                 proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0)),
                 proto.ButtonRequest(code=proto_types.ButtonRequest_ConfirmOutput),
                 proto.ButtonRequest(code=proto_types.ButtonRequest_SignTx),
@@ -123,7 +127,7 @@ class TestMultisig(common.TrezorTest):
         # Let's do a second signature with key 3
         inp3 = proto_types.TxInputType(
             address_n=[3],
-            prev_hash=binascii.unhexlify('c6091adf4c0c23982a35899a6e58ae11e703eacd7954f588ed4b9cdefc4dba52'),
+            prev_hash=TXHASH_c6091a,
             prev_index=1,
             script_type=proto_types.SPENDMULTISIG,
             multisig=multisig,
@@ -132,10 +136,10 @@ class TestMultisig(common.TrezorTest):
         with self.client:
             self.client.set_expected_responses([
                 proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0)),
-                proto.TxRequest(request_type=proto_types.TXMETA, details=proto_types.TxRequestDetailsType(tx_hash=binascii.unhexlify("c6091adf4c0c23982a35899a6e58ae11e703eacd7954f588ed4b9cdefc4dba52"))),
-                proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=binascii.unhexlify("c6091adf4c0c23982a35899a6e58ae11e703eacd7954f588ed4b9cdefc4dba52"))),
-                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=binascii.unhexlify("c6091adf4c0c23982a35899a6e58ae11e703eacd7954f588ed4b9cdefc4dba52"))),
-                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=1, tx_hash=binascii.unhexlify("c6091adf4c0c23982a35899a6e58ae11e703eacd7954f588ed4b9cdefc4dba52"))),
+                proto.TxRequest(request_type=proto_types.TXMETA, details=proto_types.TxRequestDetailsType(tx_hash=TXHASH_c6091a)),
+                proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=TXHASH_c6091a)),
+                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=TXHASH_c6091a)),
+                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=1, tx_hash=TXHASH_c6091a)),
                 proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0)),
                 proto.ButtonRequest(code=proto_types.ButtonRequest_ConfirmOutput),
                 proto.ButtonRequest(code=proto_types.ButtonRequest_SignTx),
@@ -237,7 +241,7 @@ class TestMultisig(common.TrezorTest):
         # Let's go to sign with key 10, which is NOT in pubkeys
         inp1 = proto_types.TxInputType(
             address_n=[10],
-            prev_hash=binascii.unhexlify('c6091adf4c0c23982a35899a6e58ae11e703eacd7954f588ed4b9cdefc4dba52'),
+            prev_hash=TXHASH_c6091a,
             prev_index=1,
             script_type=proto_types.SPENDMULTISIG,
             multisig=multisig,
diff --git a/tests/device_tests/test_op_return.py b/tests/device_tests/test_op_return.py
index 2db586d..a065103 100644
--- a/tests/device_tests/test_op_return.py
+++ b/tests/device_tests/test_op_return.py
@@ -58,10 +58,10 @@ class TestOpReturn(common.TrezorTest):
         with self.client:
             self.client.set_expected_responses([
                 proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0)),
-                proto.TxRequest(request_type=proto_types.TXMETA, details=proto_types.TxRequestDetailsType(tx_hash=binascii.unhexlify("d5f65ee80147b4bcc70b75e4bbf2d7382021b871bd8867ef8fa525ef50864882"))),
-                proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=binascii.unhexlify("d5f65ee80147b4bcc70b75e4bbf2d7382021b871bd8867ef8fa525ef50864882"))),
-                proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=1, tx_hash=binascii.unhexlify("d5f65ee80147b4bcc70b75e4bbf2d7382021b871bd8867ef8fa525ef50864882"))),
-                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=binascii.unhexlify("d5f65ee80147b4bcc70b75e4bbf2d7382021b871bd8867ef8fa525ef50864882"))),
+                proto.TxRequest(request_type=proto_types.TXMETA, details=proto_types.TxRequestDetailsType(tx_hash=TXHASH_d5f65e)),
+                proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=TXHASH_d5f65e)),
+                proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=1, tx_hash=TXHASH_d5f65e)),
+                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=TXHASH_d5f65e)),
                 proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0)),
                 proto.ButtonRequest(code=proto_types.ButtonRequest_ConfirmOutput),
                 proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=1)),
@@ -105,10 +105,10 @@ class TestOpReturn(common.TrezorTest):
         with self.client:
             self.client.set_expected_responses([
                 proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0)),
-                proto.TxRequest(request_type=proto_types.TXMETA, details=proto_types.TxRequestDetailsType(tx_hash=binascii.unhexlify("d5f65ee80147b4bcc70b75e4bbf2d7382021b871bd8867ef8fa525ef50864882"))),
-                proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=binascii.unhexlify("d5f65ee80147b4bcc70b75e4bbf2d7382021b871bd8867ef8fa525ef50864882"))),
-                proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=1, tx_hash=binascii.unhexlify("d5f65ee80147b4bcc70b75e4bbf2d7382021b871bd8867ef8fa525ef50864882"))),
-                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=binascii.unhexlify("d5f65ee80147b4bcc70b75e4bbf2d7382021b871bd8867ef8fa525ef50864882"))),
+                proto.TxRequest(request_type=proto_types.TXMETA, details=proto_types.TxRequestDetailsType(tx_hash=TXHASH_d5f65e)),
+                proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=TXHASH_d5f65e)),
+                proto.TxRequest(request_type=proto_types.TXINPUT, details=proto_types.TxRequestDetailsType(request_index=1, tx_hash=TXHASH_d5f65e)),
+                proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0, tx_hash=TXHASH_d5f65e)),
                 proto.TxRequest(request_type=proto_types.TXOUTPUT, details=proto_types.TxRequestDetailsType(request_index=0)),
                 proto.Failure()
             ])