Mike, you will find many threads on the forum about this topic.
Plug-it cords come in two gauges. One of them is keyed to make sure you don't use an underrated cord with a tool that has higher power requirements.
Basically, one is a thinner, lighter gauge cord for tools with smaller motors. The other is a heavier gauge for tools with bigger motors and power requirements.
The heavier gauge cord, which is not keyed, can be used on all tools.
Shane