This means that items dropped by the player can be destroyed after a set time.
Go to the BP_MasterItem and create a new function called Destroy Timer and copy the image below.
Next create 2 new variables in the BP_MasterItem first one called Destroy Time and set it to a Float and the default value to 999 (This is the number of seconds after being spawned the item will be destroyed) Create another variable called Use Destroy Time and set it to a Bool type. Set the default value to true if you want to use this feature.
Next copy the highlighted nodes shown in the image, location at the top of the screenshot.