diff --git a/lazer/sdk/js/examples/index.ts b/lazer/sdk/js/examples/index.ts
index 3c3ea22657..21c9d734ea 100644
--- a/lazer/sdk/js/examples/index.ts
+++ b/lazer/sdk/js/examples/index.ts
@@ -52,7 +52,7 @@ await client.subscribe({
   subscriptionId: 1,
   priceFeedIds: [1, 2],
   properties: ["price"],
-  chains: ["solana"],
+  formats: ["solana"],
   deliveryFormat: "binary",
   channel: "fixed_rate@200ms",
   parsed: false,
@@ -63,7 +63,7 @@ await client.subscribe({
   subscriptionId: 2,
   priceFeedIds: [1, 2, 3, 4, 5],
   properties: ["price", "exponent", "publisherCount", "confidence"],
-  chains: ["evm"],
+  formats: ["evm"],
   deliveryFormat: "json",
   channel: "fixed_rate@200ms",
   parsed: true,
diff --git a/lazer/sdk/js/package.json b/lazer/sdk/js/package.json
index 37bd04d0e4..ac165e0b0c 100644
--- a/lazer/sdk/js/package.json
+++ b/lazer/sdk/js/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@pythnetwork/pyth-lazer-sdk",
-  "version": "0.3.3",
+  "version": "0.4.0",
   "description": "Pyth Lazer SDK",
   "publishConfig": {
     "access": "public"
diff --git a/lazer/sdk/js/src/client.ts b/lazer/sdk/js/src/client.ts
index 755b426129..3626757aff 100644
--- a/lazer/sdk/js/src/client.ts
+++ b/lazer/sdk/js/src/client.ts
@@ -2,13 +2,11 @@ import WebSocket from "isomorphic-ws";
 import { dummyLogger, type Logger } from "ts-log";
 
 import {
-  BINARY_UPDATE_FORMAT_MAGIC,
-  EVM_FORMAT_MAGIC,
-  PARSED_FORMAT_MAGIC,
+  BINARY_UPDATE_FORMAT_MAGIC_LE,
+  FORMAT_MAGICS_LE,
   type ParsedPayload,
   type Request,
   type Response,
-  SOLANA_FORMAT_MAGIC_BE,
 } from "./protocol.js";
 import { WebSocketPool } from "./socket/websocket-pool.js";
 
@@ -17,6 +15,8 @@ export type BinaryResponse = {
   evm?: Buffer | undefined;
   solana?: Buffer | undefined;
   parsed?: ParsedPayload | undefined;
+  leEcdsa?: Buffer | undefined;
+  leUnsigned?: Buffer | undefined;
 };
 export type JsonOrBinaryResponse =
   | {
@@ -64,9 +64,9 @@ export class PythLazerClient {
         });
       } else if (Buffer.isBuffer(data)) {
         let pos = 0;
-        const magic = data.subarray(pos, pos + UINT32_NUM_BYTES).readUint32BE();
+        const magic = data.subarray(pos, pos + UINT32_NUM_BYTES).readUint32LE();
         pos += UINT32_NUM_BYTES;
-        if (magic != BINARY_UPDATE_FORMAT_MAGIC) {
+        if (magic != BINARY_UPDATE_FORMAT_MAGIC_LE) {
           throw new Error("binary update format magic mismatch");
         }
         // TODO: some uint64 values may not be representable as Number.
@@ -81,12 +81,16 @@ export class PythLazerClient {
           pos += UINT16_NUM_BYTES;
           const magic = data
             .subarray(pos, pos + UINT32_NUM_BYTES)
-            .readUint32BE();
-          if (magic == EVM_FORMAT_MAGIC) {
+            .readUint32LE();
+          if (magic == FORMAT_MAGICS_LE.EVM) {
             value.evm = data.subarray(pos, pos + len);
-          } else if (magic == SOLANA_FORMAT_MAGIC_BE) {
+          } else if (magic == FORMAT_MAGICS_LE.SOLANA) {
             value.solana = data.subarray(pos, pos + len);
-          } else if (magic == PARSED_FORMAT_MAGIC) {
+          } else if (magic == FORMAT_MAGICS_LE.LE_ECDSA) {
+            value.leEcdsa = data.subarray(pos, pos + len);
+          } else if (magic == FORMAT_MAGICS_LE.LE_UNSIGNED) {
+            value.leUnsigned = data.subarray(pos, pos + len);
+          } else if (magic == FORMAT_MAGICS_LE.JSON) {
             value.parsed = JSON.parse(
               data.subarray(pos + UINT32_NUM_BYTES, pos + len).toString()
             ) as ParsedPayload;
diff --git a/lazer/sdk/js/src/protocol.ts b/lazer/sdk/js/src/protocol.ts
index 8ca021232f..e698d7b88d 100644
--- a/lazer/sdk/js/src/protocol.ts
+++ b/lazer/sdk/js/src/protocol.ts
@@ -1,4 +1,4 @@
-export type Chain = "evm" | "solana";
+export type Format = "evm" | "solana" | "leEcdsa" | "leUnsigned";
 export type DeliveryFormat = "json" | "binary";
 export type JsonBinaryEncoding = "base64" | "hex";
 export type PriceFeedProperty =
@@ -16,7 +16,7 @@ export type Request =
       subscriptionId: number;
       priceFeedIds: number[];
       properties: PriceFeedProperty[];
-      chains: Chain[];
+      formats: Format[];
       deliveryFormat?: DeliveryFormat;
       jsonBinaryEncoding?: JsonBinaryEncoding;
       parsed?: boolean;
@@ -71,9 +71,16 @@ export type Response =
       parsed?: ParsedPayload | undefined;
       evm?: JsonBinaryData | undefined;
       solana?: JsonBinaryData | undefined;
+      leEcdsa?: JsonBinaryData | undefined;
+      leUnsigned?: JsonBinaryData | undefined;
     };
 
-export const BINARY_UPDATE_FORMAT_MAGIC = 1_937_213_467;
-export const PARSED_FORMAT_MAGIC = 2_584_795_844;
-export const EVM_FORMAT_MAGIC = 706_910_618;
-export const SOLANA_FORMAT_MAGIC_BE = 3_103_857_282;
+export const BINARY_UPDATE_FORMAT_MAGIC_LE = 461_928_307;
+
+export const FORMAT_MAGICS_LE = {
+  JSON: 3_302_625_434,
+  EVM: 2_593_727_018,
+  SOLANA: 2_182_742_457,
+  LE_ECDSA: 1_296_547_300,
+  LE_UNSIGNED: 1_499_680_012,
+};