The Nub V3 is more compact, restrictive and more secure for an absolute discretion. The tube is now extended closer to the body increasing the effectiveness of the chastity. The tube facing downward also discourages the stimulant and motivating a prolong use of the devices.
If you know the circumference of your genital, refer to the chart below for recommended ring size. To find the circumference, place a string around the genital (behind the testicles and base of the shaft). The string should be snug but not tight cutting the blood circulation. We recommend that you measure only after a hot shower. Using simple math, divide your measurement with pi (3.142).