Q: Is the device effective to improve premature ejaculation?
A: Of course, yes
If you use auto Jelq device, organ and scrotum are consistently rubbed, so that is effective to dull sense of glans. Which means that helps to improve premature ejaculation.
If you want to see more improvement, when you tie, tie the part lightly where glans and genital meet for more consistent rub. So, you will experience the improvement of premature ejaculation.