For 26\", 27.5\"(650B) & 700c wheels with disc brakesA wrap-around seat structure creates a virtual cocoon of protection and features an updated shoulder harness with a multiple height adjustment system. An innovative suspension system cushions bumps and jolts and the integrated roll bar gives extra head protection and doubles as a carrying handle. Adjustable footrests and straps keep small feet away from spinning wheels. Child seat complies with stringent European, CPSIA and Proposition 65 safety standards.The included heavy-duty disc mount rack features an innovative BabySeat™ attachment that requires no tools to attach and remove seat from rack. Once the seat is removed, the exposed QuickTrack™ system is compatible with all Topeak MTX TrunkBags and MTX Rear Baskets.Seat Body :Molded engineering grade plastic.Safety Features : Adjustable foot rests with straps,Roll bar handle,Shoulder harness with multiple height adjustment system,Full body cocoon,Rear reflector.Suspension :Dual steel spring.Rack :6061 T-6 hollow aluminum.Max. Weight :Capacity (BabySeat) 22 kg / 48.5 lb.Max. Weight :Capacity (Rack) 25 kg / 55 lb.Bag Compatibility :MTX QuickTrack™ system.Size (L x W x H)  : 58.5 x 39.5 x 77.4 cm,23” x 15.5” x 30.5” (Seat),34 x 23 x 40 cm,13.4” x 9” x 15.7” (Disc Rack).Weight :3.13 kg / 6.9 lb (Seat),630 g / 1.38 lb (Disc Rack).