Hi!
I bought the german quality extender PenimasterPro with a vacuum cup. The system is quite expensive but I experience quite high quality in the details. The system has three sizes of the silicon parts used to fit the glance into the cup. green - small, yellow - medium and blue - large. It is very important to use the right silicon parts that fits the size of your glance. AND the silicon parts have a life time of 10 days. After that they are stretched and don’t fit your glance anymore which results in poor grip of the glance and pain full session. Spare silicon parts can be bought from the manufacture of the extender.
The product comes with a belt that I use during work hours. I work at an office and sit most of the day, I reattach the cup every hour at which I do some Firegoatrolls to ease up on my glance.
In total I stretch the penis moderately ( less is more ) around 8 hours a day. If I am up to it I extend the time at evenings using the spring extender ( with cup ). 1 - 2 hours with more force adding to the total time up to 10 hours. This is done with no serious problem. It works really well. In addition I do some jelqing and kegels each day.
Being able to wear the stretching belt during work hours is really neat I must say.
I read that some have had problems with vacuum cups but I do think it is the best I have tried. I have tried nose grip before and I hated it as it hurts. The vacuum cup, if handed right, does not hurt at all.
/ Soulmedeep