They claim to invest your bitcoin or some select altcoins for you. You transfer your crypto into their wallet on www.bi-options.tech. They have 3 plans. Depending on what plan you select, they claim you can withdraw your crypto after maturity which takes a given time usually over 24 hours. They claim to pay interest again depending on what plan you choose. I received $5 on top of my $100 worth in bitcoin. So next time, I reinvested $180, but when I tried to withdraw it, after over 24 hours, they refused to let me withdraw saying that I should add more money to jump into the next plan which would allow me to withdraw multiple times. When I said I needed my money back, they insisted my money is safe in their wallet. That was the end of it for me. DON'T REPEAT MY MISTAKE. Don't waste your money on these pathetic thieves.