diff --git a/README.md b/README.md
index 0d844db..125590c 100644
--- a/README.md
+++ b/README.md
@@ -57,7 +57,7 @@ npm i @orionprotocol/sdk
 import { OrionUnit } from "@orionprotocol/sdk";
 import { Wallet } from "ethers";
 
-const orionUnit = new OrionUnit("bsc", "production"); // eth, bsc, ftm available
+const orionUnit = new OrionUnit("bsc", "production"); // eth, bsc, ftm, polygon, okc available
 const wallet = new Wallet("0x...", orionUnit.provider);
 // OrionUnit is chain-in-environment abstraction
 ```
diff --git a/src/constants/chains.ts b/src/constants/chains.ts
index 761709e..de3abfa 100644
--- a/src/constants/chains.ts
+++ b/src/constants/chains.ts
@@ -1,4 +1,16 @@
 import { SupportedChainId } from '../types';
 
-export const developmentChains = [SupportedChainId.BSC_TESTNET, SupportedChainId.ROPSTEN, SupportedChainId.FANTOM_TESTNET];
-export const productionChains = [SupportedChainId.MAINNET, SupportedChainId.BSC, SupportedChainId.FANTOM_OPERA];
+export const developmentChains = [
+  SupportedChainId.BSC_TESTNET,
+  SupportedChainId.ROPSTEN,
+  SupportedChainId.FANTOM_TESTNET,
+  SupportedChainId.POLYGON_TESTNET,
+  SupportedChainId.OKC_TESTNET,
+];
+export const productionChains = [
+  SupportedChainId.MAINNET,
+  SupportedChainId.BSC,
+  SupportedChainId.FANTOM_OPERA,
+  SupportedChainId.POLYGON,
+  SupportedChainId.OKC,
+];