If you intent to trade in Equity Derivatives Segment, you have to come through the custodial route. You will need to open NRO Custody Account. Brokers like Zerodha and ProStocks offer NRO Custody account from ISSL, which is IL&FS Group Company. Your settlement obligation for trades in Equity Derivatives Segment will be done by ISSL from your custody account. ISSL charges custody account management charges and you need to do KYC with ISSL also. Your Broker will assist you in opening your custody account with ISSL. ISSL will permit custody account with assets not less than USD 5000.