Insulin syringe holder

It's an insulin syringe holder to help one to make an insulin injection easier - to prevent the needle from coming too deep under the skin... NOTE: the photos with a syringe are only for illustration purposes, it's an elder model, that has restrainer position misaligned, so the needle looks to stand out too much. The actual model doesn't have that mistake, but I didn't have a syringe to make a new photo. The photo without a syringe is a right one.

One of my friends, who suffer from diabetes,