SparkPool Asic Question Settings Setup

[MZ4]

I have a little bit stupid question.

The correct Pool Settings to mine ETH with Asic is:
URL : stratum+tcp://stratum-eth-usa.sparkpool.com:3333
Worker: wallet/sub_account
Password: ?

OR

URL : stratum+tcp://stratum-eth-usa.sparkpool.com:3333
Worker: sub_account/wallet
Password: ?

OR

URL : stratum+tcp://stratum-eth-usa.sparkpool.com:3333
Worker: sub_account
Password: ?

I know it sound a little bit stupid but I can not understand the correct setup for Worker.