diff --git a/packages/electron-chrome-web-store/src/browser/index.ts b/packages/electron-chrome-web-store/src/browser/index.ts
index 7445cc5..b11e566 100644
--- a/packages/electron-chrome-web-store/src/browser/index.ts
+++ b/packages/electron-chrome-web-store/src/browser/index.ts
@@ -4,7 +4,7 @@ import * as path from 'path'
 import { registerWebStoreApi } from './api'
 import { loadAllExtensions } from './loader'
 export { loadAllExtensions } from './loader'
-export { installExtension } from './installer'
+export { installExtension, downloadExtension } from './installer'
 import { initUpdater } from './updater'
 export { updateExtensions } from './updater'
 import { getDefaultExtensionsPath } from './utils'
diff --git a/packages/electron-chrome-web-store/src/browser/installer.ts b/packages/electron-chrome-web-store/src/browser/installer.ts
index 9b781ac..9ff6526 100644
--- a/packages/electron-chrome-web-store/src/browser/installer.ts
+++ b/packages/electron-chrome-web-store/src/browser/installer.ts
@@ -174,7 +174,13 @@ export async function downloadExtensionFromURL(
   }
 }
 
-async function downloadExtension(extensionId: string, extensionsDir: string): Promise<string> {
+/**
+ * Download and unpack extension to the given extensions directory.
+ */
+export async function downloadExtension(
+  extensionId: string,
+  extensionsDir: string,
+): Promise<string> {
   const url = getExtensionCrxURL(extensionId)
   return await downloadExtensionFromURL(url, extensionsDir, extensionId)
 }