diff --git a/v6/gateway/index.ts b/v6/gateway/index.ts
index eb08db47..fdd5a454 100644
--- a/v6/gateway/index.ts
+++ b/v6/gateway/index.ts
@@ -590,7 +590,7 @@ export interface GatewayHeartbeat {
 export interface GatewayIdentifyProperties {
 	$os: string;
 	$browser: string;
-	device: string;
+	$device: string;
 }
 
 /**