Yes, the Motorola TLKR T82 Extreme set of 4 (Quad Pack) can easily be supplemented with the set of 2 (Twin Pack) to form a group of 6 people. Here are the reasons why this is possible:

- Both sets use the same technology and frequency band (PMR446), which allows for more compatible communication between the devices.
- The radios have the same functions, including easy pairing, which makes it easier to join the devices in a group.

Therefore, you can use the set of 4 and the set of 2 together to form a group of 6 people.