The HRN-CT20T11 is an OBDII adapter for the 2019 Tesla Model 3 year and for the 2020 Tesla Model 3, to connect to the Tesla OBDII engine diagnostics port. This has been confirmed to work on the Tesla Model Y as well.
If you are looking for an OBDII port adapter for the 2018 Tesla Model 3, you need to purchase the HRN-CT20T1. See the image below to verify the correct adapter.
Length: 30 cm / 12 inches
Max length of connected cables: 2 meters / 6.5 feet
Other Tesla Adapters
2018 Tesla Model 3 OBDII Adapter