diff --git a/src/main/ua-parser.d.ts b/src/main/ua-parser.d.ts
index b837831..03be97a 100644
--- a/src/main/ua-parser.d.ts
+++ b/src/main/ua-parser.d.ts
@@ -8,7 +8,7 @@ declare namespace UAParser {
         is(val: string): boolean;
         toString(): string;
         withClientHints(): PromiseLike<T> | T;
-        withFeatureCheck(): T;
+        withFeatureCheck(): PromiseLike<T> | T;
     }
 
     interface IBrowser extends IData<IBrowser> {
diff --git a/test/dts-test.ts b/test/dts-test.ts
index edf1d47..0f05a8a 100644
--- a/test/dts-test.ts
+++ b/test/dts-test.ts
@@ -32,8 +32,8 @@ expectType<'crawler' | 'cli' | 'email' | 'fetcher' | 'inapp' | 'mediaplayer' | '
 expectType<boolean>(browser.is(''));
 expectType<string>(browser.toString());
 expectType<IBrowser | PromiseLike<IBrowser>>(browser.withClientHints());
-expectType<IBrowser>((<IBrowser>browser.withClientHints()).withFeatureCheck());
-expectType<boolean>((<IBrowser>browser.withClientHints()).withFeatureCheck().is(''));
+expectType<IBrowser | PromiseLike<IBrowser>>((<IBrowser>browser.withClientHints()).withFeatureCheck());
+expectType<boolean>((<IBrowser>(<IBrowser>browser.withClientHints()).withFeatureCheck()).is(''));
 
 expectType<ICPU>(parser.getCPU());
 expectType<IDevice>(parser.getDevice());