diff --git a/led/client.ts b/led/client.ts
index a84e3694f..ff53c40f4 100644
--- a/led/client.ts
+++ b/led/client.ts
@@ -133,6 +133,8 @@ namespace modules {
         //% callInDebugger
         //% group="Light"
         //% weight=95
+        //% blockId=jacdac_led_num_pixels
+        //% block="%led number of pixels"
         numPixels(): number {
             this.start()
             const values = this._numPixels.pauseUntilValues() as any[]