Sport buggy recommended minimum age new born pushchair weight 96 kg reversible seat carrycots car seat carrycot pushchair seat backrest 3 positions harness system 5 point safety harness slider adjustable folding mechanism one hand fold collapsible self standing wheel settings swivelling lockable wheel type eva tyres wheel diameter rear 24 cm wheel diameter front 16 cm number of wheels 4 safety bar with bumper bar footrest adjustable dimensi