Complex sentence: In the late 1960's, a device specification known as CU/AL (meaning copper-aluminum) was created that specified standards for devices intended for use with aluminum wire, including larger undercut screw terminals to more securely hold the wire.
Split into simpler sentences: In the late 1960's, a device specification known as CU/AL (meaning copper-aluminum) was created that specified standards for devices intended for use with aluminum wire. Some of these devices used larger undercut screw terminals to more securely hold the wire.