This product is for GLU test or other tests that you have blood needed. It is attractive to add semiopaque pen casing with smooth and streamline appearance. There are 5 power options could be set. You can choose any injection depth what you want. This product can be used in any hospitals, clinics and houses. Anyone can use it except children. It's refined, light and easy to use. There are a instroction manual inside in each packing. You want to know more details, please contact us soon. Thank you!!