One clever accessoryIf you buy or already have an Urban Iki Front seat, you already have one of these but with an extra Front mounting block, you can easily transfer the bicycle seat from one bicycle to another. When you go out without your little one, you just take of the seat in secondsFits both A Head (minimum of 19mm after removing spacers) and Quill style stemsThe Front mounting block is for mounting your Urban Iki Front seat and the Urban Iki Windscreen