diff --git a/tmux.conf b/tmux.conf
index cb30311..af3c136 100644
--- a/tmux.conf
+++ b/tmux.conf
@@ -3,9 +3,6 @@ set-option -ga  mouse
 # https://github.com/seebi/tmux-colors-solarized/blob/master/tmuxcolors-256.conf
 set-option -g status-style bg=colour235,fg=colour136,default # bg=base02, fg=yellow
 
-# set window split
-bind-key b split-window
-
 # default window title colors
 set-window-option -g window-status-style fg=colour244,bg=default,dim # fg=base0
 
@@ -104,3 +101,5 @@ bind-key V choose-window 'join-pane -h -s "%%"'
 bind-key W choose-window 'swap-window -t "%%"'
 
 bind A command-prompt "rename-window "%%""
+
+bind C customize-mode