diff --git a/src/index.js b/src/index.js
index 3316c42..8a61ca7 100644
--- a/src/index.js
+++ b/src/index.js
@@ -301,7 +301,7 @@ export class Component extends HTMLElement {
    * @param value<String|Boolean|Number>
    */
   #prop2attr(name, value) {
-    let options = this.#getPropOptions(name)
+    let options = this.#getPropOptions(name) || {}
     let attrName = options.attrName
 
     if (options.attribute === false) {
@@ -344,15 +344,18 @@ export class Component extends HTMLElement {
     propName = camelize(name)
 
     options = this.#getPropOptions(propName)
-    value = fixedValue(value, options)
 
-    if (options.attribute === false) {
-      if (value === null) {
-        return
-      }
-      if (value === this[propName]) {
-        this.removeAttribute(name)
-        return
+    if (options) {
+      value = fixedValue(value, options)
+
+      if (options.attribute === false) {
+        if (value === null) {
+          return
+        }
+        if (value === this[propName]) {
+          this.removeAttribute(name)
+          return
+        }
       }
     }