https://www.youtube.com/watch?v=O2ySMRcd2bM
1.5mm for slight leeches size 22/20/18
2.0mm for slight leeches size 18/16
2.4mm for slight leeches size 14/12
2.7mm for slight leeches size 12/10
3.3mm for leeches size 10/8
3.8mm for leeches size 10/8/6
