This optional set of Mobility Wheels is designed for exclusive use with the Pango Pediatric Activity Chairs. The Wheels allow the chair and child to be safely moved across the classroom or clinic room or from room to room. To use the Mobility Wheels, the chair stabilizers, which are available separately, need to be attached to the chair first. Please note, this is a set of 4 Optional Mobility Wheels only. The Pango Pediatric Activity Chair is available separately. The Pango is CE marked and meets the essential requirements of all relevant European Medical Device Directives. No assembly required. Open the box and simply and easily attach the Wheels to the stabilizers in the pre-drilled holes. These Wheels fit both the Small and Medium sized Pango Activity Chairs. The front two wheels swivel allowing easy maneuverability and the back two lock, ensuring the chair stays put when needed. The wheels work best on smooth, indoor floors. While they will work outdoors, it is not recommended they be used there.