system
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human
What does SPEC PREP mean?
gpt
On till system the spec prep button is used so you can add custom messages for food, IE "special prep" my till system used to have loads of standard stuff like gluten free and nut allergy so you didn't have to type. For anything specific you would use spec prep. 

It stands out so that in the middle of service it stands out for chef's to see when checking the ticket.

Basically it's a button that lets you add a custom comment