---
title: Swing
description: "Play 0x3F, client → server."
---

`play` · `0x3F` · **serverbound** (client → server)

Sent when the player swings an arm (attack, block break, or use). `hand` is main or off hand. The server relays the animation to nearby players via `Animate`; it does not itself cause damage or interaction.

Sent by the client, read by the server. Listen for it with `client.on("Swing", (data) => …)` on the receiving side.

## Fields

| Field | Type | Notes |
|---|---|---|
| `hand` | VarInt |  |

## Send it

```ts
await client.sendPacket("Swing", {
  hand: /* VarInt */,
});
```

Field aliases listed under Notes are accepted as alternative keys when writing.

Source: [`src/Core/Versions/776/Packets/play/serverbound/Swing.ts`](https://github.com/GDLev/mc-protocol/blob/master/src/Core/Versions/776/Packets/play/serverbound/Swing.ts)