# Product Code Conventions Certain special characters or combinations of characters are used by the TouchPOS and therefore **CAN NOT** be used in the Product Code of an item.

Character	Reason
-	Used for Credits, Payouts and Discounts.
$	Used to indicate a Tender Amount.
.	Used for Serial Number items (Bikes, Watches Electronic Equipment etc) and issue control of Magazines.
^	Used for Operator Cards.
27	Used for Customer Loyalty Card barcodes. Must be a valid EAN13 or EAN8 barcode.
%	Used for Customer Loyalty Cards using a Mag Strip Reader.
"	Double quotes cannot be used in Product Code or Description of the item. The Barcode Label printer uses this character as part of its data and it will cause a print failure of the Label.
\\	Affects some barcode label printers and should be avoided.
+	Used as part of the Bill of Materials section to combine items into a single unit.
?	Used as part of the Bill of Materials section to search for items during the buildup process.
\*	Used as the separator for Qty and Price.

Do not use “**double quote**" anywhere. You can substitute two single quotes which appears on the screen and reports as though it is a double quote. In other words, avoid using special characters in the product code. Use standard characters A-Z and numbers 0-9. Space is acceptable as well. An exception is macro products such as bulk lotto tickets or newspapers. They usually start with: #