Arch Revolution Patented ANTI-SLIDE,QUICK-WINDING BOBBINS.

Fits for Singer®:
66,99,185,192,201,242,247,248,252,
257,258,259,285,292,327,328,329,337,
338,353,354,360,362,367,368,401,403,
404,413,416,417,418,457,466,476,477,
478,500,502,503,507,509,513,514,518,
522,527,533,534,538,560,734,774,776