diff --git a/docs/reference/commandline/service_create.md b/docs/reference/commandline/service_create.md
index e69cc2e6..1bb1ea62 100644
--- a/docs/reference/commandline/service_create.md
+++ b/docs/reference/commandline/service_create.md
@@ -170,7 +170,8 @@ node type label equals queue:
 ```bash
 $ docker service create \
   --name redis_2 \
-  --constraint node.labels.type == queue
+  --constraint 'node.labels.type == queue' \
+  redis:3.0.6
 ```
 
 ## Related information