Ptil Techeiles supplies the entire set in one box, white strings and techeiles strings together, so nothing has to be matched up from two sources. The wool is dyed, spun and plied by hand, and the shezira is done expressly for the purpose of tzitzis rather than pulled from general stock.Two decisions come with the order. The first is the shitah: Rambam, where one string is techeiles and the rest white, or Raavad, which calls for a different count on the corner. Ask a rav which your family follows before ordering, since the packets are cut accordingly and are not interchangeable. The second is thickness. Thick strands hold up to daily wear on a tallis katan and stay presentable much longer; thin strands lie flatter and are what many men want on a tallis gadol that is put on and folded away each morning.One set covers all four corners. If this is a first attempt at tying with techeiles, have a set of plain white strings on hand as well and practice the chulyos on those before touching the blue. Material: Wool Strings: Rambam, Raavid Type: Thick, Thin Sold by Judaica Square, Lakewood NJ. Free shipping on orders over $75. Returns within 15 days.