Hi @Kerem.Tatlici, it appears that torchvision.models.detection was not supported yet in torchvision v0.2.2:
https://github.com/pytorch/vision/tree/v0.2.2/torchvision/models
I recommend to install newer torchvision version (and if necessary, upgrade PyTorch) to get the torchvision detection models. You can find the instructions for installing PyTorch/torchvision on Jetson in this topic: