The max recommended user weight is 220lbs. Users weighing more than 220lbs will have impacted top speeds and ranges in some edge cases but will not impact the safety and integrity of the product.
You can use Moonwalkers like everyone else if you are happy with slightly reduced performance in edge cases like reaching 90%+ of the top speed at the steepest hill.
Moonwalkers come in one size, and best fit US Men’s 9 to 12 (EU 41 to 45) and US Women’s 10.5 to 13.5. For shoe sizes larger than our recommended range, comfort is reduced due to your toe being extended a bit over Moonwalkers. In beta testing, we tested down to a Women's size 7 and up to a Men's size 14, where they had no issues Moonwalking.