Making sure your ring fits is a crucial part of the ring shopping process. All Patrick Adair Designs Rings are Sized in US Universal sizes. If you are unsure of your ring size please order our Free Ring Sizer fist. To Find a US Size Conversion chart, visit our helpful blog post here. We do not offer free size exchanges for custom rings. The Tungsten Glowstone Ring is NOT eligible for a free size exchange. If you're ring isn't a perfect fit, contact us at firstname.lastname@example.org, and we will be more than happy to find a solution for you.