This collection from KinkLab features 3 nickel-plated steel cock rings for a perfect fit in any variation of ways youft.d like to wear them. Designed to create larger, harder erections. Product Details: Ring sizes: 2” (5cm), 1.75” (4.5 cm), and 1.5” (3.8 cm). Safe to use with any kind of lubricant. Not safe for nickel allergies.