diff --git a/lib/storage.js b/lib/storage.js
index 6f20d4f..4e333f5 100644
--- a/lib/storage.js
+++ b/lib/storage.js
@@ -35,10 +35,6 @@ var opKey = function(key) {
 
 var MAX_TS = _.repeat('9', 14);
 
-var opKeyTs = function(key) {
-  return key ? '!' + zeroPad(key, 14) : '';
-};
-
 
 var KEY = {
   WALLET: function(walletId) {