By default, miners who connect to Slush Pool while mining with Braiins OS+ will not pay any pool fees. 

If you choose to mine with Slush Pool while using Braiins OS+, you’ll receive a full rebate on the pool fee collected. In other words, Slush Pool still collects the standard 2% fee at the time of mining, but all of it is sent back to you at a scheduled date each month. The rebate is distributed automatically on the first Monday of every month.