diff --git a/pytest-embedded-idf/pytest_embedded_idf/serial.py b/pytest-embedded-idf/pytest_embedded_idf/serial.py
index 0d644a54..4d168b62 100644
--- a/pytest-embedded-idf/pytest_embedded_idf/serial.py
+++ b/pytest-embedded-idf/pytest_embedded_idf/serial.py
@@ -156,7 +156,7 @@ def flash(self, app: Optional[IdfApp] = None) -> None:
                 elif v:
                     _args.append(f'--{k}')
             else:
-                _args.append(f'--{k.replace("_", "-")}')
+                _args.append(f'--{k}')
                 if k == 'after':
                     _args.append('hard_reset')
                 else:
diff --git a/pytest-embedded-serial-esp/pyproject.toml b/pytest-embedded-serial-esp/pyproject.toml
index 01574b39..671729c8 100644
--- a/pytest-embedded-serial-esp/pyproject.toml
+++ b/pytest-embedded-serial-esp/pyproject.toml
@@ -32,8 +32,7 @@ requires-python = ">=3.7"
 
 dependencies = [
     "pytest-embedded-serial~=1.17.0a2",
-    "esptool>=4.9,<5; python_version<'3.10'",
-    "esptool>=5.1.dev1,<6; python_version>='3.10'",
+    "esptool~=4.9",
 ]
 
 [project.urls]