Wire diameters, gauges and length of wire per spool:
0.1mm / 0.004" - 42 SWG, 30 meters, ;
0.2mm / 0.0076" - 36 SWG, 20 meters;
0.3mm / 0.0128" - 30 SWG, 10 meters;
0.5mm / 0.0196" - 25 SWG, 6 meters. Handling hint: you can break the 0.1mm and 0.2mm wire by simply flexing it repeatedly and pulling apart; no need to damage scissors.