Another place four digits is used is paper receipts of credit card payments for example - http://salesreceiptstore.com/fake_store_receipts/fake_credit_card_cust

Another place four digits is used is paper receipts of credit card payments for example - http://salesreceiptstore.com/fake_store_receipts/fake_credit_card_customer_copy_receipts.jpg http://salesreceiptstore.com/fake_store_receipts/fake_credit...