SINGER 2139 Class 66 Bobbins, Metal, 4-Count,
This set of 4 class 66 metal bobbins serve as replacements for the following compatible machines: brands compatible with Singer models 66-1 through 66-18, 99CL, 185, 192, 201, 609, 717, and other top drop-in bobbin sewing machines. Consult your machine's manual to ensure correct bobbin size. Use the bobbins beneath the needle plate in automatic sewing machines to wind the thread for your embroidery projects. Never add thread to a partially wound bobbin, as it may be uneven and cause thread to tangle or break.