Tools—Lay
The lay tool allows you to place a bet of a specific size at a specific price at an exact time. You can set it to say lay £50 @ (any price) and then set the hours, minutes and seconds before OR after the start of the event. You can see in this screenshot we have Evo set to lay a horse called Ask The Oracle for £50 at 3.00 exactly 10 seconds AFTER the scheduled start time. If the price is below 3.00 when the bet is submitted you will get the best available price below 3.00. If the price is above 3.00 then the bet will sit unmatched and when the market suspends it will cancel.

You will notice in the picture the button with the + is selected. That means AFTER the start of the event and – means BEFORE. Hover the mouse over these buttons for confirmation. When the – is selected EVO waits until the exact time selected before the market goes in play to submit the bet.
As you can see in the screenshot you can also select Fill/kill, Stop Loss and Tick Offset. If you select Fill/Kill then the bet will cancel after a time set by you (see Fill or Kill tool). If you select stop loss then once the bet is placed it will also place a stop loss set by you in stop loss tool.
If you select Tick Offset, then once the bet activates, and is matched, it will place a tick offset according to your tick offset tool settings.
The lay tool will also allow you to lay the entire field at a set price before or after the race. Here we lay every runner for £100 @ 1.20 5 seconds after the race starts. My maximum risk is £20 and if we get 2 matched we win £60 and three matched we win £160. A great option for 5f and 6f handicaps where you expect a tight finish.

Watch a video of the Lay tool in action here.