Quad rollers that can be worn over shoes. Used, but in good condition. Designed for riding on asphalt and relatively flat surfaces. Easy to put on and take off thanks to the locking mechanism. Adjustable for shoe sizes 31-35, depending on the sneaker size; if they are canvas shoes, a larger size will fit. If worn on a bare foot, they fit me at 42.5. They have brakes on both the right and left rollers. Spring mechanism. ABEC-5 bearings. Wheel diameter 80 mm. 100 GEL, Grand Mall area, Metrocity