diff --git a/lib/bcoin/pool.js b/lib/bcoin/pool.js
index bfbd0864..fc6d7da9 100644
--- a/lib/bcoin/pool.js
+++ b/lib/bcoin/pool.js
@@ -745,7 +745,7 @@ Pool.prototype.unwatch = function unwatch(id) {
 // See "Filter matching algorithm":
 // https://github.com/bitcoin/bips/blob/master/bip-0037.mediawiki
 Pool.prototype.isWatched = function(tx, bloom) {
-  var i, input, output, outHash;
+  var i, input, output, prev;
 
   if (!bloom)
     bloom = this.bloom;
@@ -775,19 +775,19 @@ Pool.prototype.isWatched = function(tx, bloom) {
   // 4. Test data elements in input scripts
   for (i = 0; i < tx.inputs.length; i++) {
     input = tx.inputs[i];
-    outHash = input.out.hash;
+    prev = input.out.hash;
 
-    if (typeof outHash === 'string')
-      outHash = utils.toArray(outHash, 'hex');
+    if (typeof prev === 'string')
+      prev = utils.toArray(prev, 'hex');
 
     // Test the prev_out tx hash
-    if (bloom.test(outHash))
+    if (bloom.test(prev))
       return true;
 
     // Test the prev_out script
     if (input.out.tx) {
-      output = input.out.tx.outputs[input.out.index];
-      if (testScript(output.script))
+      prev = input.out.tx.outputs[input.out.index];
+      if (testScript(prev.script))
         return true;
     }