You can choose to have these instructions to remain open for the following durations:
DAY. Stop Limit order remains open through the end of the trading day and will expire if the trigger price is not reached before the current day's market close.
GTW. Stop Limit order remains open though the end of the week and will expire if the trigger price is not reached after seven calendar days.
GTM. Stop Limit order remains open though the end of the month and will expire if the trigger price is not reached after thirty calendar days.
Once the trigger price is reached, the stop limit order becomes a regular limit order to buy or sell.The limit order must be filled before the end of day, after which the order will expire if not fulfilled.