I have a BOM with a column for weight and some parts are in pounds and some are in grams and I would like to create another column in the BOM that tells you what the units of the mass is for each part  because without it you don't know which part is in pounds or which one is in grams. I tried adding another column set to the custom property of Unit Of Measure but all the rows in the column were just blank.... Does anyone know how to do this?  I have SW2012.