Clear plastic bobbin case with die-cut foam insert that grips bobbins securely to stop unwinding. The extra-large slots accommodate Class M bobbins used in long-arm, mid-arm and many embroidery machines. A strong front latch helps keep the box spill-proof in storage or transport. Fits most bobbins up to approximately 25 mm (1") diameter and keeps colors and thread types easy to sort at a glance.