I have been enjoying this forum and learning from it for awhile now and figured that it was about time that I share some info as well. I found these boxes at Joanne's Fabrics, I think that they were around $3.25 a piece and I picked them up on a 30% off sale. The purple button on the end is a spring loaded slide lock, when the button is depressed any one of the compartments can be opened. Each of the compartments has a snap lid so that when the lock button is depressed the individual boxes do not just pop opened. The front bottom corner of each compartment also has a radius to make it easy to get hooks or beads out and the bottom side of the unit has small little legs that allow multiple box units to stack nicely. Hope that this helps, happy tying!
