diff --git a/common.go b/common.go
index 1cacfdd8..dd6b61bd 100644
--- a/common.go
+++ b/common.go
@@ -83,7 +83,7 @@ func readElement(r io.Reader, element interface{}) error {
 		return nil
 
 	// Message header command.
-	case *[commandSize]uint8:
+	case *[CommandSize]uint8:
 		_, err := io.ReadFull(r, e[:])
 		if err != nil {
 			return err
@@ -233,7 +233,7 @@ func writeElement(w io.Writer, element interface{}) error {
 		return nil
 
 	// Message header command.
-	case [commandSize]uint8:
+	case [CommandSize]uint8:
 		_, err := w.Write(e[:])
 		if err != nil {
 			return err
diff --git a/internal_test.go b/internal_test.go
index 6f332712..5663e05f 100644
--- a/internal_test.go
+++ b/internal_test.go
@@ -31,10 +31,6 @@ const (
 	// MaxCountSetSubVer makes the internal maxCountSetSubVer constant
 	// available to the test package.
 	MaxCountSetSubVer = maxCountSetSubVer
-
-	// CommandSize makes the internal commandSize constant available to the
-	// test package.
-	CommandSize = commandSize
 )
 
 // TstRandomUint64 makes the internal randomUint64 function available to the
diff --git a/message.go b/message.go
index d5b51ea0..7d4da72f 100644
--- a/message.go
+++ b/message.go
@@ -16,9 +16,9 @@ import (
 // checksum 4 bytes.
 const MessageHeaderSize = 24
 
-// commandSize is the fixed size of all commands in the common bitcoin message
+// CommandSize is the fixed size of all commands in the common bitcoin message
 // header.  Shorter commands must be zero padded.
-const commandSize = 12
+const CommandSize = 12
 
 // MaxMessagePayload is the maximum bytes a message can be regardless of other
 // individual limits imposed by messages themselves.
@@ -157,7 +157,7 @@ func readMessageHeader(r io.Reader) (int, *messageHeader, error) {
 
 	// Create and populate a messageHeader struct from the raw header bytes.
 	hdr := messageHeader{}
-	var command [commandSize]byte
+	var command [CommandSize]byte
 	readElements(hr, &hdr.magic, &command, &hdr.length, &hdr.checksum)
 
 	// Strip trailing zeros from command string.
@@ -193,11 +193,11 @@ func WriteMessageN(w io.Writer, msg Message, pver uint32, btcnet BitcoinNet) (in
 	totalBytes := 0
 
 	// Enforce max command size.
-	var command [commandSize]byte
+	var command [CommandSize]byte
 	cmd := msg.Command()
-	if len(cmd) > commandSize {
+	if len(cmd) > CommandSize {
 		str := fmt.Sprintf("command [%s] is too long [max %v]",
-			cmd, commandSize)
+			cmd, CommandSize)
 		return totalBytes, messageError("WriteMessage", str)
 	}
 	copy(command[:], []byte(cmd))