Slotted anodized bobbin from T.ART Products.
The bobbin features twisted slots creating an open structure.
They have 2ba threads on both sides allowing you to use them unviversally with virtually most brands of line clips, weights and chains.
Due to the open structure, an isotope of .... can be found in the bobbin. be placed without having to glue them. The bobbins fit 3x15mm isotopes which fall in generously.
The bobbin weighs 10 grams and is 15mmx30mm.