The Hareline Foamanizer Thread Module has a die cut base with long posts to hold thread, tinsel, floss, wire and Antron . This module attaches the side of a tool base to keep thread in a handy place. Each post holds 5 standard spools. UK or sewing machine spools also fit allowing you to stack Pearsalls type spools. For those that use the old metal spools those spools also fit. The Gudebrod and the long sewing machine spools will likely fit too for all you folks into Euro tinsel.