diff --git a/setup.py b/setup.py
index 312fdca..2acd9b9 100644
--- a/setup.py
+++ b/setup.py
@@ -46,7 +46,7 @@ setup(
   platforms='any',
   license='MIT',
   install_requires=[
-    'libusb1 >= 1.6.4',
+    'libusb1 == 1.6.6',
     'hexdump >= 3.3',
     'pycrypto >= 2.6.1',
     'tqdm >= 4.14.0',