diff --git a/modules/plugins/flexboxOld.js b/modules/plugins/flexboxOld.js
index 21fccfa..6e51f76 100644
--- a/modules/plugins/flexboxOld.js
+++ b/modules/plugins/flexboxOld.js
@@ -34,7 +34,7 @@ export default function flexboxOld({ property, value, styles, browserInfo: { bro
     if (!keepUnprefixed && !Array.isArray(styles[property])) {
       delete styles[property]
     }
-    if (property === 'flexDirection') {
+    if (property === 'flexDirection' && typeof value === 'string') {
       return {
         WebkitBoxOrient: value.indexOf('column') > -1 ? 'vertical' : 'horizontal',
         WebkitBoxDirection: value.indexOf('reverse') > -1 ? 'reverse' : 'normal'
diff --git a/modules/static/plugins/flexboxOld.js b/modules/static/plugins/flexboxOld.js
index f2b8800..b9d37c2 100644
--- a/modules/static/plugins/flexboxOld.js
+++ b/modules/static/plugins/flexboxOld.js
@@ -14,7 +14,7 @@ const alternativeProps = {
 }
 
 export default function flexboxOld(property, value) {
-  if (property === 'flexDirection') {
+  if (property === 'flexDirection' && typeof value === 'string') {
     return {
       WebkitBoxOrient: value.indexOf('column') > -1 ? 'vertical' : 'horizontal',
       WebkitBoxDirection: value.indexOf('reverse') > -1 ? 'reverse' : 'normal'