Slim old school style bobbins made from white or black PTFE for the classic look. 35mm x 8.50mm in size with 3 center windows slots for an internal isotope mounting. The weight of the bobbin itself is 5g and is a M5 thread, available as heads only and full kits. (no Isotope fitted) Bobbins take a 3.0 x 22.5 Isotope or smaller
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