Polaris PT6 Al Pin Terminal Copper Pin 6 AWG
https://nsiindustries.com/product/polaris-pt6-al-pin-terminal-copper-pin-6-awg/
These copper pin aluminum connectors are rated for aluminum conductors with a pigtail type copper pin designed to facilitate termination of aluminum conductors into copper connectors. The POLARIS compression design creates a permanent, vibration-resistant connection that you can rely on with low contact resistance.