My Last Say in This Best penis extender Review There is no product capable of producing miracles. If you want to increase your length, you have to do whatever it takes to achieve your goal. Do the penis exercises, and I am sure that it will give you a firmer erection than if you simply rely on penis extenders alone. X4 labs is a great product because of its improved comfort technology, and it encourages you to perform the penile exercises. I hope my Best penis extender review clarifies the confusion about the product’s efficacy.