diff --git a/src/interfaces/RouterInterface.ts b/src/interfaces/RouterInterface.ts
new file mode 100644
index 00000000..6c5a3139
--- /dev/null
+++ b/src/interfaces/RouterInterface.ts
@@ -0,0 +1,59 @@
+export interface Operation {
+  /**
+   * used only for FixedRate or Dispenser, but needs to be filled even for pool
+   * @type {string}
+   */
+  exchangeIds: string
+  /**
+   * pool Address
+   * @type {string}
+   */
+  source: string
+  /**
+   * operation:
+   * 0 - swapExactAmountIn
+   * 1 - swapExactAmountOut
+   * 2 - FixedRateExchange
+   * 3 - Dispenser
+   * @type {number}
+   */
+  operation: number
+  /**
+   * token in address
+   * @type {string}
+   */
+  tokenIn: string
+  /**
+   * when swapExactAmountIn is EXACT amount IN
+   * expressed in Wei
+   * @type {string | number}
+   */
+  amountsIn: string | number
+  /**
+   * token out address
+   * @type {string}
+   */
+  tokenOut: string
+  /**
+   * when swapExactAmountIn is MIN amount OUT
+   * expressed in Wei
+   * @type {string | number}
+   */
+  amountsOut: string | number
+  /**
+   * max price (only for pools)
+   * expressed in Wei
+   * @type {string | number}
+   */
+  maxPrice: string | number
+  /**
+   * swap fee amount
+   * @type {string}
+   */
+  swapMarketFee: string
+  /**
+   * market fee address to receive fees
+   * @type {string}
+   */
+  marketFeeAddress: string
+}
diff --git a/src/interfaces/index.ts b/src/interfaces/index.ts
index 185f4770..447a29d4 100644
--- a/src/interfaces/index.ts
+++ b/src/interfaces/index.ts
@@ -2,3 +2,4 @@ export * from './FixedRateInterface'
 export * from './PoolInterface'
 export * from './Erc20Interface'
 export * from './DispenserInterface'
+export * from './RouterInterface'
diff --git a/src/pools/Router.ts b/src/pools/Router.ts
index bef064c2..e71c063a 100644
--- a/src/pools/Router.ts
+++ b/src/pools/Router.ts
@@ -3,18 +3,8 @@ import Web3 from 'web3'
 import { TransactionReceipt } from 'web3-core'
 import { AbiItem } from 'web3-utils'
 import defaultRouter from '@oceanprotocol/contracts/artifacts/contracts/pools/FactoryRouter.sol/FactoryRouter.json'
-import { LoggerInstance, getFairGasPrice } from '../utils'
-
-interface Operations {
-  exchangeIds: string
-  source: string
-  operation: number
-  tokenIn: string
-  amountsIn: string | number
-  tokenOut: string
-  amountsOut: string | number
-  maxPrice: string | number
-}
+import { getFairGasPrice } from '../utils'
+import { Operation } from '../interfaces/RouterInterface'
 
 /**
  * Provides an interface for FactoryRouter contract
@@ -49,10 +39,10 @@ export class Router {
   /**
    * Estimate gas cost for buyDTBatch method
    * @param {String} address
-   * @param {Operations} operations Operations objects array
+   * @param {Operation} operations Operations objects array
    * @return {Promise<TransactionReceipt>} Transaction receipt
    */
-  public async estGasBuyDTBatch(address: string, operations: Operations[]): Promise<any> {
+  public async estGasBuyDTBatch(address: string, operations: Operation[]): Promise<any> {
     const gasLimitDefault = this.GASLIMIT_DEFAULT
     let estGas
     try {
@@ -68,12 +58,12 @@ export class Router {
   /**
    * BuyDTBatch
    * @param {String} address
-   * @param {Operations} operations Operations objects array
+   * @param {Operation} operations Operations objects array
    * @return {Promise<TransactionReceipt>} Transaction receipt
    */
   public async buyDTBatch(
     address: string,
-    operations: Operations[]
+    operations: Operation[]
   ): Promise<TransactionReceipt> {
     const estGas = await this.estGasBuyDTBatch(address, operations)
 
diff --git a/src/pools/balancer/Pool.ts b/src/pools/balancer/Pool.ts
index 3a351f21..768ec0d7 100644
--- a/src/pools/balancer/Pool.ts
+++ b/src/pools/balancer/Pool.ts
@@ -353,7 +353,7 @@ export class Pool {
     const pool = new this.web3.eth.Contract(this.poolABI, poolAddress)
     let result = null
     try {
-      result = await pool.methods._marketCollector().call()
+      result = await pool.methods._publishMarketCollector().call()
     } catch (e) {
       this.logger.error(`ERROR: Failed to get marketFeeCollector address: ${e.message}`)
     }
@@ -509,7 +509,7 @@ export class Pool {
     const pool = new this.web3.eth.Contract(this.poolABI, poolAddress)
     let weight = null
     try {
-      const result = await pool.methods.publishMarketFee(token).call()
+      const result = await pool.methods.publishMarketFees(token).call()
       weight = await this.unitsToAmount(token, result)
     } catch (e) {
       this.logger.error(`ERROR: Failed to get market fees for a token: ${e.message}`)
diff --git a/test/unit/pools/Router.test.ts b/test/unit/pools/Router.test.ts
index 480f0116..c373e401 100644
--- a/test/unit/pools/Router.test.ts
+++ b/test/unit/pools/Router.test.ts
@@ -16,7 +16,7 @@ import { LoggerInstance } from '../../../src/utils'
 import { NFTFactory, NFTCreateData } from '../../../src/factories/NFTFactory'
 import { Router } from '../../../src/pools/Router'
 import { BigNumber } from 'bignumber.js'
-import { Erc20CreateParams, PoolCreationParams } from '../../../src/interfaces'
+import { Erc20CreateParams, PoolCreationParams, Operation } from '../../../src/interfaces'
 const { keccak256 } = require('@ethersproject/keccak256')
 const web3 = new Web3('http://127.0.0.1:8545')
 const communityCollector = '0xeE9300b7961e0a01d9f0adb863C7A227A07AaD75'
@@ -292,7 +292,7 @@ describe('Router unit test', () => {
     // 1 - swapExactAmountOut
     // 2 - FixedRateExchange
     // 3 - Dispenser
-    const operations1 = {
+    const operations1: Operation = {
       exchangeIds: keccak256('0x00'), // used only for FixedRate or Dispenser, but needs to be filled even for pool
       source: pool1, // pool Address
       operation: 0, // swapExactAmountIn
@@ -300,10 +300,12 @@ describe('Router unit test', () => {
       amountsIn: web3.utils.toWei('1'), // when swapExactAmountIn is EXACT amount IN
       tokenOut: erc20Token,
       amountsOut: web3.utils.toWei('0.1'), // when swapExactAmountIn is MIN amount OUT
-      maxPrice: web3.utils.toWei('10') // max price (only for pools)
+      maxPrice: web3.utils.toWei('10'), // max price (only for pools),
+      swapMarketFee: web3.utils.toWei('0.1'),
+      marketFeeAddress: contracts.accounts[0]
     }
 
-    const operations2 = {
+    const operations2: Operation = {
       exchangeIds: keccak256('0x00'), // used only for FixedRate or Dispenser, but needs to be filled even for pool
       source: pool2, // pool Address
       operation: 0, // swapExactAmountIn
@@ -311,7 +313,9 @@ describe('Router unit test', () => {
       amountsIn: web3.utils.toWei('1'), // when swapExactAmountIn is EXACT amount IN
       tokenOut: erc20Token2,
       amountsOut: web3.utils.toWei('0.1'), // when swapExactAmountIn is MIN amount OUT
-      maxPrice: web3.utils.toWei('10') // max price (only for pools)
+      maxPrice: web3.utils.toWei('10'), // max price (only for pools)
+      swapMarketFee: web3.utils.toWei('0.1'),
+      marketFeeAddress: contracts.accounts[0]
     }
 
     await router.buyDTBatch(user2, [operations1, operations2])