diff --git a/src/rx/rx.h b/src/rx/rx.h
index 016fe7db28..e73bc27c6f 100644
--- a/src/rx/rx.h
+++ b/src/rx/rx.h
@@ -637,7 +637,7 @@ struct rx_ackPacket {
 #define	RX_ACK_PING_RESPONSE	7	/* Ack'ing because we were pinged */
 #define	RX_ACK_DELAY		8	/* Ack generated since nothing has happened since receiving packet */
 #define RX_ACK_IDLE             9	/* Similar to RX_ACK_DELAY, but can 
-					 * be */
+					 * be used to compute RTT */
 
 /* Packet acknowledgement type */
 #define	RX_ACK_TYPE_NACK	0	/* I Don't have this packet */