HDAero offers several FAA certified STC’s, including:

STC Number: SA4004SW
Modification Kit to install a 21-inch camera port in the Cessna U206G and the TU206G. An optional floor plug and outer seal plate will be available to install when the camera is not installed. There is an Optional FWD Mount and Side Mount for the Camera Port. The airplane can be returned to its normal passenger or cargo configuration.
Limitations and Conditions:
The installer must determine whether this design change is compatible with previously approved modification.
This modification is for structural approval only.
If the holder agrees to permit another person to use this certificate to alter the product, the holder shall give the other person written evidence of that permission.

STC SA4525SW
Modification Kit to the Cessna 210N, T210N for the installation of a 18.5 inch long x 20 inch wide Aft Baggage Camera Port compartment camera ports and view ports.
Limitations and Conditions:
Compatibility of this modification with other previously approved modifications must be determined by the installer.
If the holder agrees to permit another person to use this certificate to alter the product, the holder shall give the person written evidence of permission.

STC Number: SA4968SW
Modification Kit to the Cessna T210M, T210N, 210M, 210N to install a 16 x 21 inch recessed camera port at the co-pilot seat location. An optional floor plug is available to install when the camera is not installed to the airplane can be returned to its normal passenger configuration.
Limitations and Conditions:
Provisions only for camera installation.
The installer must determine whether this design change is compatible with previously approved modifications.
If the holder agrees to permit another person to use this certificate to alter a product, the holder must give the other person written evidence of that permission.