It looks like a plastic hand.
You can do 2 things:
- Use stock photography. For example, we did a pregnancy tester so we looked up pregancy tester or diabetes lancet devices to find acceptable hands holding actual products that were the approximate size.
- Take your own photos. Find somebody with nice hands and have them hold a physical prototype or something roughly the same size. If you set up the lighting correctly you shouldn’t have to do too much PSD.