diff --git a/bundle/bundle--mk.el b/bundle/bundle--mk.el
index f362cbd7..d49ee26c 100644
--- a/bundle/bundle--mk.el
+++ b/bundle/bundle--mk.el
@@ -520,5 +520,12 @@ an ALIAS and SERVICE as arguments and call
 
 (global-set-key (kbd "<f12>") 'mk/toggle-frame-decorations)
 
+(defun mk/set-frame-size-85x50 ()
+  "Set the current frame's size to 85 columns by 50 rows."
+  (interactive)
+  (set-frame-size (selected-frame) 85 50))
+
+(global-set-key (kbd "C-<f12>") #'mk/set-frame-size-85x50)
+
 (provide 'bundle-mk)
 ;;; bundle-mk.el ends here