Following is a chart of industry chain thickness designations based on the number in their SKU (60,120,280, etc)

 

Chain Thickness Gauges*
60	2.6mm
80	3mm
100	4mm
120	4.8mm
150	4.8mm
180	7mm
210	7.6mm
250	9.4mm

^* Chain thickness measurements may vary from these but these are a good guideline.