diff --git a/wpa_supplicant/wpa_supplicant.conf b/wpa_supplicant/wpa_supplicant.conf
index 3358250a6..629d88600 100644
--- a/wpa_supplicant/wpa_supplicant.conf
+++ b/wpa_supplicant/wpa_supplicant.conf
@@ -962,6 +962,9 @@ fast_reauth=1
 # 0  = Enable MAX-AMSDU if hardware supports it.
 # 1  = Disable AMSDU
 #
+# ampdu_factor: Maximum A-MPDU Length Exponent
+# Value: 0-3, see 7.3.2.56.3 in IEEE Std 802.11n-2009.
+#
 # ampdu_density:  Allow overriding AMPDU density configuration.
 #  Treated as hint by the kernel.
 # -1 = Do not make any changes.