diff --git a/sshm.bash b/sshm.bash
index 1298ffc..2d1dc70 100755
--- a/sshm.bash
+++ b/sshm.bash
@@ -81,7 +81,7 @@ ssh_manager_connect() {
   if [[ "$host" =~ ^[0-9]+$ ]]; then
     local host_name
     host_name=$(grep -E '^Host ' "$config_file" | awk '{print $2}' | grep -v '^#' | sed -n "${host}p")
-    if [ -n "$host_name" ]]; then
+    if [[ -n "$host_name" ]]; then
       ssh -F "$config_file" "$host_name"
     else
       echo "Invalid number." 1>&2