Standard Durability: These needles should be replaced after 5-6 hours of actual sewing or embroidery time. Large Embroidery Eye: The large embroidery eye prevents thread breakage and fraying. Use with 40 weight or heavier embroidery thread. Works well for metallics. Size: A size 80/12 needle is appropriate for medium to heavy weight fabrics. Type: The sharp tip of the needle pierces woven fibers for a perfect stitch. Use: This needle is perfect for medium to heavy weight wovens like chambray, tr