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.