diff --git a/src/main/java/dev/openfga/sdk/api/client/ApiClient.java b/src/main/java/dev/openfga/sdk/api/client/ApiClient.java
index 85063a0..6f45391 100644
--- a/src/main/java/dev/openfga/sdk/api/client/ApiClient.java
+++ b/src/main/java/dev/openfga/sdk/api/client/ApiClient.java
@@ -67,6 +67,24 @@ public ApiClient() {
         asyncResponseInterceptor = null;
     }
 
+    /**
+     * Create an instance of ApiClient.
+     * <p>
+     * In other contexts, note that any settings in a {@link Configuration}
+     * will take precedence over equivalent settings in the
+     * {@link HttpClient.Builder} here.
+     *
+     * @param builder Http client builder.
+     */
+    public ApiClient(HttpClient.Builder builder) {
+        this.builder = builder;
+        this.mapper = createDefaultObjectMapper();
+        this.client = this.builder.build();
+        interceptor = null;
+        responseInterceptor = null;
+        asyncResponseInterceptor = null;
+    }
+
     /**
      * Create an instance of ApiClient.
      * <p>
@@ -177,7 +195,7 @@ protected String getDefaultBaseUri() {
     }
 
     protected HttpClient.Builder createDefaultHttpClientBuilder() {
-        return HttpClient.newBuilder();
+        return HttpClient.newBuilder().version(HttpClient.Version.HTTP_1_1);
     }
 
     /**
diff --git a/src/test/java/dev/openfga/sdk/api/client/ApiClientTest.java b/src/test/java/dev/openfga/sdk/api/client/ApiClientTest.java
index c584d04..67a6e46 100644
--- a/src/test/java/dev/openfga/sdk/api/client/ApiClientTest.java
+++ b/src/test/java/dev/openfga/sdk/api/client/ApiClientTest.java
@@ -16,6 +16,8 @@
 import static org.junit.jupiter.api.Assertions.assertNotEquals;
 
 import java.net.http.HttpClient;
+
+import org.checkerframework.checker.units.qual.A;
 import org.junit.jupiter.api.Test;
 
 class ApiClientTest {
@@ -35,4 +37,10 @@ public void newHttpClientWhenBuilderModified() {
 
         assertNotEquals(client1, apiClient.getHttpClient());
     }
+
+    @Test
+    public void httpClientShouldUseHttp1ByDefault() {
+        ApiClient apiClient = new ApiClient();
+        assertEquals(apiClient.getHttpClient().version(), HttpClient.Version.HTTP_1_1);
+    }
 }