What Conductors Cannot Be Used With Screwless Pressure Terminals Of The Conductor Push In Type?

What Conductors Cannot Be Used With Screwless Pressure Terminals Of The Conductor Push In Type? Screwless pressure terminal connectors of the conductor push-in type are for use only with solid copper and copper-clad aluminum conductors. What is the largest conductor that shall be permitted to be connected by means of wire-binding screws? In accordance with