Tick the tickbox "Is Secondary Unit" for the secondary unit of measure in the POS product and choose the secondary UOM.

It will auto take a secondary unit of measure when you add product first time.

Price and tax will auto count based on the unit price.

Press "Change UOM" to change the unit of measure.

After press on that button UOM list open, you can choose the UOM here.

After the change unit of measure, UOM & qty will be updated.

Price and tax will auto count based on the pricelist.

You can see both Qty and both UOM in the POS order.

We provide the below configurations,

1) You can choose the default UOM type from "UOM Settings" for the default unit of measure.
2) Enable the "Display UOM In Receipt" to print UOM in the receipt.

Here we choose the default UOM type: Primary. and you have to tick "Display UOM In Receipt" to print that UOM in receipt.

Now we create an order.

So by default selected UOM type comes.

The receipt with UOM.

Now we choose the default UOM type: Secondary & tick "Display UOM In Receipt" to print that UOM in receipt.

Now we make an order.

So by default selected UOM type comes.

Selected UOM type comes in receipt.

Enable "Display Price In Secondary UOM".

Products with secondary UOM price.

Receipt with secondary UOM price.