This is a hard question to answer. The best option if you have the time is to utilize both techniques. Clamping is an advance technique and takes more discipline and experience. We recommend starting with the Zen Pump and slowly introducing clamping into your routine. It takes a while to perfect clamping but once you master the technique of manual blood flow control with a clamp it is great exercise to promote erection strength and control. Pumping is great for beginners and advanced users. Penis pumping gets you used to the feeling and exercise of pumping additional blood into your penis. Both penis clamping and penis pumping are great ways to make penis girth gains.