The NEW MATRIX WIZARD 24 mixed variety are medical grade, which is made from high-quality colored monofilament and braided materials. Non-absorbable Suture Threads Silk (black): 2/0, 3/0, 4/0, 5/0 Nylon (black): : 2/0, 3/0, 4/0, 5/0 Nylon (blue): 2/0, 3/0, 4/0, 5/0 Polyester (green): 2/0, 3/0, 4/0, 5/0 Polypropylene (blue): 2/0, 3/0, 4/0, 5/0 Absorbable Suture Threads Chromic Catgut: 2/0, 3/0, 4/0, 5/0 It comes with a pre-attached stainless steel (rustproof) reverse cutting needle, which is excellent for traversing tough materials, pigskin, suture pads, rubber or silicon anatomical models. This educational device is great for people who want to master suturing in preparation for real-life emergencies, required hospital related skills, classroom experiments. Medical, Veterinary, EMTs, Medic, Physician Assistant and Nursing students will find this new product as a useful addition to their practice suture kits. In addition to this, these tools are also great for Medical / Surgical hospital student's clinic rotations, college biology class, anatomy subjects, laboratory activities and taxidermy. The training suture set is so handy that you can easily put in your learning backpack or add as an accessory for teaching dissection set. Wound stitching and knot tying are fun once one has mastered the art of suturing. Not for clinical use. Four distinct needle sizes: