The phone used in the picture is a OnePlus 3T with an Otterbox case. Dimension of the phone with case are: - 81mm wide - 13mm thick Useful for phones that are between 80mm and 93mm wide. You can use a bigger phone, but this will make the spring rub against the parts. Once printed, just slide the two pieces into eachother and attach a spring on the two little bars. The spring can't be wider than 8mm and should be around 25mm long when not stretched. There's a cavity for a nut in the lower part which allows you to attach it to a normal tripod thread with a 1/4-20 UNC nut. As i was unable to find this nut at my local hardware store, i decided to print it. This model is also in the documents so you can print it yourself and don't have to go out searching for one! I have put two little rubber tabs on the inside of the clamps so that the phone doesn't slide out. If you're planning on doing this, please check if your phone will still fit, as it wil decrease the maximum width of the phones that will fit!