> For the complete documentation index, see [llms.txt](https://docs.blockrazor.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.blockrazor.io/streams/node-stream/robinhood-chain/direct-sequencer-feed-ultra.md).
# Robinhood Chain Direct Sequencer Feed(Ultra)
This section introduces services, price and integration methods of the BlockRazor Robinhood Chain Direct Sequencer Feed.
### What Is the Direct Sequencer Feed(Ultra)?
Direct Sequencer Feed (Ultra) is an ultra-low-latency data transmission solution built on the [Standard version](/streams/node-stream/robinhood-chain/direct-sequencer-feed.md). It deeply optimizes network routing and underlying transmission mechanisms to further reduce the end-to-end latency of Sequencer Feed delivery.
Powered by BEF technology, the Ultra version provides access to the latest block data at exceptional speed—without requiring users to deploy or operate a node.
The solution is purpose-built for advanced sniping and copy-trading strategies where timing is critical. It enables trading systems to capture on-chain activity earlier and secure valuable time for strategy computation and transaction execution—turning every microsecond into a competitive advantage.
### Price
The price is $200 per unit per day and $2000 per unit per month. Subscribe
### Endpoint
### Usage Instructions
{% stepper %}
{% step %} Subscribe **BlockRazor Sequencer Feed**
{% endstep %}
{% step %}
**Retrieve the auth from the portal and append it as the URI to the WSS URL.**
wss\://us.robinhood-feeder.blockrazor.io/ws/{authToken}
{% endstep %}
{% step %}
**Choose a WebSocket Client and Establish a WSS Connection**
Use any standard WebSocket client, such as a WebSocket library for Node.js, Go, Python, or Rust. There is no need to deploy a Robinhood Chain node or configure `--node.feed.input.url`.
{% endstep %}
{% step %}
**Receive and parse the data. The parsed data structure is as follows:**
{% code overflow="wrap" %}
```json
{
"version": 1,
"messages": [
{
"sequenceNumber": 50543784,
"message": {
"message": {
"header": {
"kind": 3,
"sender": "0xa4b000000000000000000073657175656e636572",
"blockNumber": 25872577,
"timestamp": 1788146984,
"requestId": null,
"baseFeeL1": 0
},
"l2Msg": {
"encoding": "Nitro L2 message",
"kind": 3,
"kindName": "Batch",
"decodedByteLength": 3487,
"transactionCount": 10,
"items": [
{
"index": 0,
"messageKind": 4,
"messageKindName": "SignedTx",
"messageLength": 244,
"transaction": {
"hash": "0xc4d8935f3e63b7b4…1e46fd37",
"from": "0x0dd10d651d18bc70594cb070e1117b6cd5e4a8a4",
"type": 2,
"typeName": "EIP-1559",
"chainId": 4663,
"nonce": 901,
"maxPriorityFeePerGas": 1,
"maxFeePerGas": 466288000,
"gasLimit": 120000,
"to": "0x000000000022d473030f116ddee9f6b43ac78ba3",
"value": 0,
"input": "0x87517c4500000000…6a94fc2f",
"accessList": [],
"yParity": 0,
"r": "0x1a6881f8f30266eb…090c7b15",
"s": "0x15e0901b330dfdba…0e9eb53a",
"rawTransaction": "0x02f8f08212378203…0e9eb53a"
}
},
{
"index": 2,
"messageKind": 4,
"messageKindName": "SignedTx",
"messageLength": 341,
"transaction": {
"hash": "0xef96fbbeb7072b85…6c67ee47",
"from": "0x137fe0e0fdbfe6487588f0ef842f418bbb738b8e",
"type": 0,
"typeName": "Legacy",
"chainId": 4663,
"nonce": 14,
"gasPrice": 250000000,
"gasLimit": 400000,
"to": "0xcaf681a66d020601342297493863e78c959e5cb2",
"value": 40000000000000,
"input": "0x04e45aaf00000000…00000000",
"v": 9362,
"yParity": 1,
"r": "0xe65d56b7f3eb63d7…4656bb9c",
"s": "0x4362c24ab37d7590…88c290ce",
"rawTransaction": "0xf901510e840ee6b2…88c290ce"
}
},
{
"index": 4,
"messageKind": 4,
"messageKindName": "SignedTx",
"messageLength": 119,
"transaction": {
"hash": "0x00f4bb0661c05fe8…3938c8bf",
"from": "0x6ae3de978e63b63e8486d1f495339633495d8264",
"type": 2,
"typeName": "EIP-1559",
"chainId": 4663,
"nonce": 3,
"maxPriorityFeePerGas": 234192000,
"maxFeePerGas": 542634600,
"gasLimit": 35010,
"to": "0xc45aa399aa75ace0ae56c372898abcb36d33161f",
"value": 330170416874734,
"input": "0x",
"accessList": [],
"yParity": 1,
"r": "0xdda460f047c07f2a…67caa4a0",
"s": "0x5f82128ed043cc80…4d2f6024",
"rawTransaction": "0x02f8738212370384…4d2f6024"
}
}
]
},
"l2MsgBase64": "AwAAAAAAAAD0BAL48I…jqF1iw=="
},
"delayedMessagesRead": 193164
},
"blockHash": "0x220c2e737333e10d…2e261230",
"signatureV2": "Rg3J2yhBQ8pxYUqc6e…xkNk7wA=",
"blockMetadata": null
}
]
}
```
{% endcode %}
{% endstep %}
{% endstepper %}
---
# Agent Instructions
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## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:
```
GET https://docs.blockrazor.io/streams/node-stream/robinhood-chain/direct-sequencer-feed-ultra.md?ask=&goal=
```
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