What are the best sites to get free images for ecommerce theme?

I see so many ecommerce themes in Themeforest with good images used in it. I was wondering is there any free image sites where we can find any type of good images that suites ecommerce theme?

Pixabay has quite a lot of images, you can check it out. You can also see Unsplash, but I think Pixabay has more of different kind of pics.

I am aware about these sites. But I don’t see good images that are been used in some of ecommerce themes here in themeforest. So was wondering are they using free images or paid images.

Thank you for your reply.