Strings for 3D printing Polish manufacturer Spectrum.V find a cardboard box material in vacuum packed with silica gel to absorb moisture. Box coil weighs about 1,4kgStruna is wound on the spool clear external diameter 20 cm, width 7.5 cm and a central hole 5,2cm.Průměr strings 1.75 mm (tolerance of +/- 0.05 mm)