The gap is the pool's price against the last print on Robinhood's own feed for that stock, in basis points. A positive gap means the chain is asking more than the tape last said. It is not a profit waiting to be taken: when the market is shut the chain is the only thing still pricing, and it may simply be right. The venue column is the pool that was deeper when this list was built; the trade panel quotes BOTH for your exact size and names the one it will actually send to. The round-trip column is what $1,000 costs to buy and sell again there — the fee and the depth, quoted by Uniswap itself.