diff --git a/package/mac80211/files/lib/wifi/mac80211.sh b/package/mac80211/files/lib/wifi/mac80211.sh
index efceebbe4c..6d144a95c9 100644
--- a/package/mac80211/files/lib/wifi/mac80211.sh
+++ b/package/mac80211/files/lib/wifi/mac80211.sh
@@ -209,7 +209,7 @@ enable_mac80211() {
 
 		config_get rts "$vif" rts
 		if [ -n "$rts" ]; then
-			iw phy "$phy" set rts "${frag%%.*}"
+			iw phy "$phy" set rts "${rts%%.*}"
 		fi
 
 		ifconfig "$ifname" up