diff --git a/README.md b/README.md
index 15823c5..881522b 100644
--- a/README.md
+++ b/README.md
@@ -6,7 +6,7 @@ Perl module to send ICMP ECHO REQUEST packets quickly. Original Perl module is
 available at
 http://search.cpan.org/~mlehmann/AnyEvent-FastPing-2.01/
 
-It hasn't been fully implemented original functions yet and only for IPv4 now.
+It hasn't been fully implemented original functions yet.
 
 [![GoDoc](https://godoc.org/github.com/tatsushid/go-fastping?status.svg)](https://godoc.org/github.com/tatsushid/go-fastping)
 
diff --git a/fastping.go b/fastping.go
index 9bd7fd4..0a6d903 100644
--- a/fastping.go
+++ b/fastping.go
@@ -3,8 +3,7 @@
 // available at
 // http://search.cpan.org/~mlehmann/AnyEvent-FastPing-2.01/
 //
-// It hasn't been fully implemented original functions yet and only for IPv4
-// now.
+// It hasn't been fully implemented original functions yet.
 //
 // Here is an example:
 //