P610361 Prym Bobbins. The rotary bobbin hook and the double-rotary bobbin hook are the most robust and easy-care for the majority of systems that are mainly installed in high-priced and industrial sewing machines. Prym offers the corresponding bobbins for small rotary bobbin hooks and the double-rotary bobbin hook made of metal of five units or transparent plastic of four units. The bobbins made of transparent plastic help to keep an overview of thread colours and quantity remaining, while the metal bobbins have a longer service life due to the additional robustness of their material. Manufacturers of sewing machines that use this system are, among others SINGER, DÜRR KOPP, PFAFF and CHAMPION. 610361 double rotary shuttle 21.9mm