diff --git a/protocol/p2p/sendcmpct.md b/protocol/p2p/sendcmpct.md
index e69de29..8af73af 100644
--- a/protocol/p2p/sendcmpct.md
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+# Request: SENDCMPCT
+
+This message notifies the peer that this node support Compact Block Relay. Node should only send this message after protocol version >= 70014. This message can indicate the High Bandwidth Relaying mode or Low Bandwidth Relaying mode by setting the `Mode` field. Upon recepit of this message from the peer, node should announce new block via `cmpctblock` message if `Mode = 1`, or node should announce new block via `inv` or `header` message as defined in BIP-0130. 
+
+## Format  
+
+| Field | Length | Format | Description |
+|--|--|--|--|
+| Mode | 1 byte | Integer | 1: High Bandwidth Relaying mode;</br> 0: Low Bandwidth Relaying mode;</br> Other: Invalid |
+| Version | 8 bytes | Integer<sup>[LE](..\misc\endian\little)</sup> | Must set to 1, otherwise invalid.