Sewing Machine -Metal Bobbin Case and Spools for Crochet Hook Highlights Generic Brand Metal Bobbin Case and Spools for Crochet Hook Description: Industrial Sewing Machine Spare Parts Set Made of high quality steel metal high quality, durable and anti-corrosion. Bobbins stop spinning faster, preventing the thread from unraveling or tangling when stopping and starting sewing operations. Easy to use and store, very convenient. Compatible for many old fashioned foot sewing machines. Specification: Material: Steel Size: Shuttle Bobbin: Inner Diameter: 6mm/0.24in Outer Diameter: 20mm/0.79in Height: 10mm/0.40in Bobbin Case: Diameter 30mm/1, 18 inch, height 15 mm/0.59 inch Shuttle Hook: 4.5 x 2.3 cm/1.77 x 0.91 inch Package includes: 1 Piece Shuttle Hook 1 Piece Shuttle Case 5 Piece Shuttle Coil