diff --git a/requirements.txt b/requirements.txt
index 1d6089715f9..7b0ce48be4d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -75,5 +75,4 @@ jsonrpc-requests>=0.1
 python-forecastio>=1.3.3
 
 # Firmata Bindings (*.arduino)
-PyMata>=2.07
-pyserial>=2.7
+PyMata>=2.07a