Lightweight bold colors Helps you keep track of your stitches Reminds you of what hook you were using Hinge that is easy to open and close Have you started a crochet project and put it down and forgot what size hook you were using? I have many times. So to solve this problem, I designed these stitch markers that have the size on them in millimeters and letters to remind ourselves what hook we were using. They are made using PLA filament on a 3D printer. What is PLA? Polylactide (PLA), is a thermoplastic polyester mixed with cornstarch. This is a set of 7 stitch markers and/or progress keepers. Made with round findings that have a hinge that can be opened and closed. You will receive one heart stitch marker in 3.75mm/F, 4mm/G, 5mm/H, 5.5mm/I, 6mm/J, 6.5mm/K, 8mm/L.