This Cockring apart is the 'comfort shape': the outside and inside of the ring are curved to make the Dick Ring incredibly comfortable to wear. The S-curve profile designed to fit a man's body and make your package look its largest.And when you're ready to play, this ring can keep blood in your penis, giving you longer-lasting erections and more intense orgasms.

 How to choose the most suitable size Take an inelastic line to surround the root of penis (the place is close to the belly, behind the scrotum), and then measure the length of the line, which is the perimeter, compare to the ring circumference,Please Know that choose a smaller size,If your circumference is 150mm,please choose the 143mm size. 

Width and Perimeter
 39mm/1.53inch, 125mm/4.92inch 
42mm/1.65inch, 143mm/5.63inch 
46mm/1.81inch, 153mm/6.06inch 
48mm/1.89inch, 162mm/6.37inch 
51mm/2.00inch, 172mm/6.77cinh