Might want to read this post
jelk device?
But I have to admit it did help me in my gains probably quicker than manual jelqing. But that device is expensive and the rollers when they do need replacing are almost the same cost as a new device. But trim your pubic area if you get one because it will grab the hair and don't squeeze to hard. You could cause damage or discoloration to your penis when using this device and you use too my pressure. So just be smart and careful.