I believe the blue/black parts are leather & the black straps are very long & can be wrapped around the ankle once or twice before tied to keep them from coming off the toddlers feet.There is also a pretty blue & white beaded star at the tip of these booties.
These are pre-owned but not worn very much- only a few times indoors (never outside). My guess is they would fit a child who is around a year old. The length of the bottom of the foot is 5 1/2 inches long & the opening to put the foot in is between 2- 2 1/2 inches wide.
Please let me know if you have questions. Thanks for looking!