The Pincode Checker extension allows the users to check delivery availability on the product page itself. It also has the functionality to restrict orders if the product is not available at the entered shipping address based on the settings done by the store admin.
Pincode Checker Plugin for Magento
The customers can check product availability and also whether cash on delivery payment option is available or not based on the Pincode entered. Also gives an option to the admin whether to restrict orders based on the Pincode entered or not. If the admin has set this option as enabled, the whole order will be restricted based on the product availability for a specific Pincode entered at the checkout step.
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