Description
The HRN-CT20T11 is an OBDII adapter for the 2019+ Tesla Model 3 year, to connect to the Tesla OBDII engine diagnostics port. This harness may not be compatible with an early 2019 Model 3. This has been confirmed to work on the Tesla Model Y (2019-2021) 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.

HRN-CT20T1 on the Left vs HRN-CT20T11 on the right
Length: 30 cm / 12 inches
Max length of connected cables: 2 meters / 6.5 feet
Other Tesla Adapters
2012-mid 2015 Tesla Model S OBDII Adapter
Mid 2015+ Tesla Model S OBDII Adapter
Tesla Model X OBDII Adapter
2018 Tesla Model 3 OBDII Adapter
Overview of Tesla Adapters
Geotab Features for Electric Vehicles