diff --git a/AFNetworking/AFNetworkActivityIndicatorManager.m b/AFNetworking/AFNetworkActivityIndicatorManager.m
index 4926cd2..e8db21e 100644
--- a/AFNetworking/AFNetworkActivityIndicatorManager.m
+++ b/AFNetworking/AFNetworkActivityIndicatorManager.m
@@ -23,7 +23,7 @@
 #import "AFNetworkActivityIndicatorManager.h"
 
 @interface AFNetworkActivityIndicatorManager ()
-@property (readwrite, nonatomic, assign) NSInteger activityCount;
+@property (readwrite, assign) NSInteger activityCount;
 @end
 
 @implementation AFNetworkActivityIndicatorManager