Stop Limit order is a combination of Stop order and limit order. In Stop Limit order you can place a BUY or SELL order by specifying a stop price and limit price. It will be executed at a specific price after the given Stop price has been reached which means once the order reaches the stop price, a limit order is automatically triggered to buy/sell at a specific target price.
For example
On the buy side:
If the price is currently 50 Euro and you placed a stop-limit order to buy at 55 Euro, it will wait until the price rises to 55 Euro once it reaches the price it will place a buy order.
On the sell side:
If the price is currently 50 Euro and you placed a stop-limit order to sell at 46 Euro, it will wait until the price falls to 46 Euro before it places the order automatically.
