Overview
If you're a Shopify POS customer, you may want to distinguish between your POS and web purchases.
Klaviyo syncs the source_name
when a customer completes the checkout process and creates an order in your Shopify store. According to Shopify's documentation, "source_name" is defined as:

Filter Orders by Source
You can filter Placed Order events in Klaviyo by "web," "pos," "iphone," "android," or other custom strings by using the source_name property associated with a given order. In Klaviyo, this property will appear as simply "Source Name" when you are building a segment or flow filter.
To filter and view exclusively POS Placed Order events, go to the Metrics tab of your account, click on the Placed Order metric, and filter by Source Name (equals "pos").
Segment Orders by Source
In the segment builder, you can create segments based on the Source Name property.