Tandem pushchair recommended minimum age new born pushchair weight 15 kg carrycot pushchair seat harness system 5 point safety harness slider adjustable series graco stadium duo wheel settings swivelling lockable wheel type solid rubber tyres number of wheels 4 safety bar with bumper bar footrest adjustable dimensions 100 x 60 x 113 cm dimensions folded 66 x 60 x 109 cm included in delivery canopy shopping bag footmuff bumper bar