diff --git a/src/babel/transformation/transformers/es6/block-scoping.js b/src/babel/transformation/transformers/es6/block-scoping.js
index db7bd5e959..a3ec489dc0 100644
--- a/src/babel/transformation/transformers/es6/block-scoping.js
+++ b/src/babel/transformation/transformers/es6/block-scoping.js
@@ -44,7 +44,7 @@ export function check(node) {
 export function VariableDeclaration(node, parent, scope, file) {
   if (!isLet(node, parent)) return;
 
-  if (isLetInitable(node) && file.transformers["es6.blockScopingTDZ"].canTransform()) {
+  if (isLetInitable(node) && file.transformers["es6.spec.blockScoping"].canTransform()) {
     var nodes = [node];
 
     for (var i = 0; i < node.declarations.length; i++) {
diff --git a/src/babel/transformation/transformers/es6/parameters.default.js b/src/babel/transformation/transformers/es6/parameters.default.js
index 02864c6939..5286c322dc 100644
--- a/src/babel/transformation/transformers/es6/parameters.default.js
+++ b/src/babel/transformation/transformers/es6/parameters.default.js
@@ -63,7 +63,7 @@ exports.Function = function (node, parent, scope, file) {
         param.traverse(iifeVisitor, state);
       }
 
-      if (file.transformers["es6.blockScopingTDZ"].canTransform() && param.isIdentifier()) {
+      if (file.transformers["es6.spec.blockScoping"].canTransform() && param.isIdentifier()) {
         pushDefNode(param.node, t.identifier("undefined"), i);
       }