Our Odoo is set up in Settings>Warehouse>Locations&Warehouse>Manage different units of measure for products. Are you saying this is an extra step I have to do in Developer Mode? Ive seen tutorials on how to handle selling in feet vs inches or cms, by setting a reference measure and giving the ratios of inches-to-feet or cms-to-inches. But what I want is to manage a product that is sold as a whole rod, currently configured with UOM Unit(s) and also be able to sell it as inch(es), where typically each rod measures 240 inches.

I activated Developer Mode and in Settings > Inventory I dont have that option exactly. I have the above mentioned option which is already checked and in the Product forms I can see the Unit Of Measure in the General tab and the Purchase Unit of Measure in the Procurement tab. But what I would want is to create a Sales Unit of Measure, no? We normally record these items as whole units which are 240" long, but we dont record the inches, just the whole Unit(s).