What is the difference between an OML and Interlot?

An Objectively Matched Interlot (OML) is a sale lot formed when small lines from different sources are matched on the basis of Yield, Vegetable Matter Base and Micron test results and a visual comparison of samples from each lot.

The IWTO Coretest Regulations set out limits within which the values of each of the measured parameters must fall. These limits are different for particular wool types and there are restrictions upon which wool types may be put together to form an OML. 

Interlots are matched by visual comparison only. Hence Interlots are inherently more variable than OMLs.