I bought one penis pump but don't know how it is working or not.i also don't know it is harmful for penis or not .can you tell me have any side effect?

Penis pump: It is working if you use it and get an erection. If used properly, it should not be harmful. If you truly have an erectile dysfunction (problems getting your penis hard), it is recommended to get an evaluation by a health care provider, as there are often better and more physician recommended treatments that using a pump. Best wishes.