I would like to present my new pack of 2 black greeting card mock ups. You can use it for demonstrating your illustrations, identity, postcard design and also whatever you want. Mock ups made specially for photoshop users. Here you can watch video preview about how to use mock ups in your daily work. This set made for A6 format, but you can use it for another format with same proportions.

https://creativemarket.com/Marie.Smth/1107427-2-bw-mock-ups-for-black-postcard