I have those units with all the little drawers that they sell in the hardware dept. Each drawer holds a different size needle and I also have each of my attachment feet for my sewing machine in a drawer of its own. I used my label maker to mark what is in each drawer. To keep the feet for my 3 machines separated, I use a letter system for the brand---FW for featherweight, K for Kenmore, V for Viking and MQ for my Mega Quilter. I also do the same thing with the needles.