I used these for baseball on weekends for about three months. I've only used the replacement bands about twice. They have prescription lenses, so you'll need to replace them. [Frame] Material: Front: Polyamide resin Face pad: Elastomer resin (face side) / Polyamide resin (frame side) ●ZT-301 (KIDS, for upper elementary to junior high school students) Size: Overall width: approx. 144mm, Overall height: approx. 43.5mm Lens width: 53mm, Nose width: 14mm, Lens height: 35mm