diff --git a/plugin/vim-tmux-runner.vim b/plugin/vim-tmux-runner.vim
index feaef19..1f9155e 100644
--- a/plugin/vim-tmux-runner.vim
+++ b/plugin/vim-tmux-runner.vim
@@ -204,6 +204,7 @@ endfunction
 
 function! s:RunnerDimensionSpec()
     let dimensions = join(["-p", s:vtr_percentage, "-".s:vtr_orientation])
+    return dimensions
 endfunction
 
 function! s:_ReattachPane()