Abstract: A system and method for forming changes in elevation in a concrete slab includes one or more channels having substantially parallel bottom and top edges. The bottom and top edges include bent ends and a number of spaced apertures are formed in the bottom and top edges and the bent ends. Braces are inserted into the apertures to support the channel or channels in a vertical position. On or more different type bolt holders are selectively insertable into the channels for holding āJā bolts in a vertical position, parallel to the channels. Connecting elements are included for holding adjacent ends of separate channels together.