Kit contains three rings. #14, #17, and #20. Perfect Fit has developed the first cock ring sizing system designed to fit you without too much pull but with enough restriction to be truly effective. Features Ring Number 14 1.4 inches in diameter, 4.4 inches circumference. Ring Number 17 1.7 inches in diameter, 5.3 inches circumference. Ring Number 20 2 inches in diameter, 6.3 inches circumference.