Here's some information on sizing that I hope will help you make your decision.
I recommend to my customers to trust their gut instinct when it comes to ordering the correct size. If you know that your fingers are slightly smaller or larger than the average finger size, then I would go ahead and order Small or Extra-large accordingly. If you think your fingers are of average size, then you can order Regular size. I find that almost everybody has a good sense of how big their fingers are in relation to other people and make the right decision when they order their Black Mountain slide.
The cool thing about the Black Mountain slide is that the spring-loaded arm makes it a universal fit and so you don't need the exact right size for the slide ring to fit. The plastic arm will conform to the size of your finger and make it comfortable and stable.
Here is a video we made showing how to wear your Black Mountain slide.
I hope this information helps you make your decision. If you have any other questions, don't hesitate to reach out
Here is a link to order!