When using a Stop order (STP), you only designate one price: your Stop Price.
Once your Stop Price is hit, it will trigger a market order for execution.
When using a Stop Limit order (STP LMT), you must designate two prices: a Stop Price and a Limit Price. Once your Stop Price is hit, it will trigger a limit order at the price you designated for execution.
Additional information on: Stop orders and Stop Limit orders can be found on our website.
Additional information on: the difference between a stop and a stop limit order as well as more information regarding the use of stop orders on can be found in our Knowledge Base.