From the Ideal catalog page:
Comply with N.E.C. Section #110-14(b) for aluminum-to-copper connections; UL Listed to 486C and CSA Certified to C22.2 #188; complies with Federal Specification W-S-610E
UL Listed to 467 for grounding and bonding
UL486C scope: "This Standard applies to single-polarity, hand-, or tool-applied splicing wire and cable connectors intended for use with all alloys of copper, aluminum conductors, or copper-clad aluminum conductors, or all three, in accordance with the Canadian Electrical Code Part I, CSA C22.1, in Canada, the National Electrical Code, NFPA-70, in the United States of America".