(See List below to which models these bobbins fit). NELCO MODELS - 6102FB, A-3, A-509-3, F-600, JA38, N-250B4, R-400, R-1000, R-2000, R-3000, R-4000, SZA800-L, SZA-820-L2, ZZB-1. You should always use the correct bobbin that are specifically design to fit your bobbin case.
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