The American double one touch (adot), also known as a range binary, is an option with two American barriers. You define one barrier above the underlying asset and one below it.
If during the option's lifetime the underlying asset:
Moves outside the defined range between the two barriers (i.e., either of the barriers is hit), the payout is activated. That is, the buyer of the option receives the fixed payout specified in the option on the option's delivery date in the base currency.
Does not hit either of the two defined barriers, there is no payout.