The plugs that are moulded on to leads are fine except when you want to extend them or run them through a wall or cupboard, you would have to drill a hole the size of the plug. Best to cut the plug off and drill a small hole enough for the wire to pass through. Then fit a standard three pin plug.
{Do fit the right fuse Rating for the item you are using. when finished). What`s that I hear you say, how do you do that? A skill lost. Health and safety wins.