diff --git a/.gitignore b/.gitignore
index 944e2d9..1333c2d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -33,4 +33,5 @@ Thumbs.db
 .AppleDouble
 .LSOverride
 .Spotlight-V100
-.Trashes
\ No newline at end of file
+.Trashes
+package-lock.json
diff --git a/index.js b/index.js
index d266af6..08992ab 100644
--- a/index.js
+++ b/index.js
@@ -2,10 +2,6 @@
 
 var thing = require('core-util-is');
 
-function filterUndefined(key) {
-    return !!key;
-}
-
 exports = module.exports = {
 
     /**
@@ -14,7 +10,7 @@ exports = module.exports = {
      * @param mapFn map keys, return undefined to not include.
      */
     camelize: function camelize(obj, mapFn) {
-        var newobj;
+        var newobj, keys, k;
 
         if (!mapFn) {
             mapFn = function (k) {
@@ -36,12 +32,16 @@ exports = module.exports = {
         }
         else if (thing.isObject(obj) && !Buffer.isBuffer(obj)) {
             newobj = {};
+            keys = Object.keys(obj);
 
-            Object.keys(obj).map(mapFn).filter(filterUndefined).forEach(function (key) {
-                var newkey = exports.camelCase(key);
-
-                newobj[newkey] = exports.camelize(obj[key], mapFn);
-            });
+            for (var i = 0; i < keys.length; i++) {
+                k = mapFn(keys[i]);
+                if (!k) {
+                    continue;
+                }
+                k = exports.camelCase(k);
+                newobj[k] = exports.camelize(obj[keys[i]], mapFn);
+            }
         }
         else {
             newobj = obj;
@@ -56,7 +56,7 @@ exports = module.exports = {
      * @param mapFn map keys, return undefined to not include.
      */
     underscorify: function (obj, mapFn) {
-        var newobj;
+        var newobj, keys, k;
 
         if (!mapFn) {
             mapFn = function (k) {
@@ -78,12 +78,16 @@ exports = module.exports = {
         }
         else if (thing.isObject(obj) && !Buffer.isBuffer(obj)) {
             newobj = {};
+            keys = Object.keys(obj);
 
-            Object.keys(obj).map(mapFn).filter(filterUndefined).forEach(function (key) {
-                var newkey = exports.underscore(key);
-
-                newobj[newkey] = exports.underscorify(obj[key], mapFn);
-            });
+            for (var i = 0; i < keys.length; i++) {
+                k = mapFn(keys[i]);
+                if (!k) {
+                    continue;
+                }
+                k = exports.underscore(k);
+                newobj[k] = exports.underscorify(obj[keys[i]], mapFn);
+            }
         }
         else {
             newobj = obj;
@@ -98,7 +102,7 @@ exports = module.exports = {
      * @returns {string|*}
      */
     camelCase: function camelCase(str) {
-        return str.replace(/([a-z])_(\w)/g, function (g) {
+        return str.replace(/([aA-zZ])_(\w)/g, function (g) {
             return g[0] + g[2].toUpperCase();
         });
     },
@@ -109,8 +113,10 @@ exports = module.exports = {
      * @returns {string|*}
      */
     underscore: function underscore(str) {
-        return str.replace(/([a-z])([A-Z]+)/g, function (g) {
-            return g[0] + '_' + g[1].toLowerCase();
+        return str.replace(/([a-z])([A-Z0-9]+)/g, function (g) {
+            return g.split('').map(function (k) {
+                return k.toLowerCase();
+            }).join('_');
         });
     }
 };
diff --git a/package.json b/package.json
index 625ba49..33370a5 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "camelscore",
   "description": "camelCase and under_score utilities for objects.",
-  "version": "0.1.3",
+  "version": "0.1.4",
   "author": "Trevor Livingston <tlivings@gmail.com>",
   "repository": {
     "type": "git",
diff --git a/test/test-camelscore.js b/test/test-camelscore.js
index 5fbc7ea..337ce82 100644
--- a/test/test-camelscore.js
+++ b/test/test-camelscore.js
@@ -8,7 +8,7 @@ test('test', function (t) {
     t.test('camelCase', function (assert) {
         var str = camelscore.camelCase('foo_bar');
 
-        assert.plan(4);
+        assert.plan(5);
 
         assert.strictEqual(str, 'fooBar', 'camel cased 1 underscore.');
 
@@ -16,6 +16,10 @@ test('test', function (t) {
 
         assert.strictEqual(str, 'fooBarBaz', 'camel cased 2 underscores.');
 
+        str = camelscore.camelCase('is_2FA_login');
+
+        assert.strictEqual(str, 'is2FALogin', 'camel cased 2 underscores with a caps.');
+
         str = camelscore.camelCase('_foo_bar_baz');
 
         assert.strictEqual(str, '_fooBarBaz', 'camel cased and left leading _.');
@@ -28,7 +32,7 @@ test('test', function (t) {
     t.test('underscore', function (assert) {
         var str = camelscore.underscore('fooBar');
 
-        assert.plan(4);
+        assert.plan(5);
 
         assert.strictEqual(str, 'foo_bar', 'underscore cased with 1 hump.');
 
@@ -36,6 +40,11 @@ test('test', function (t) {
 
         assert.strictEqual(str, 'foo_bar_baz', 'underscore cased with 2 humps.');
 
+        str = camelscore.underscore('is2FALogin');
+
+        //This sucks but is reality
+        assert.strictEqual(str, 'is_2_f_a_login', 'underscore cased with 2 humps and caps.');
+
         str = camelscore.underscore('_fooBaredBaz');
 
         assert.strictEqual(str, '_foo_bared_baz', 'underscore cased and left leading _.');