enKo Products Invoice Enclosed Clear Packing List Shipping Label Perfect Size - Fits Pre-Printed Shipping Labels From PayPal, Amazon, FedEx, UPS, And The U.S. Postal Service. Sticks To Multiple Surfaces - Clear Adhesive Packing List Envelope Will Stick To Cardboard, Plastic, Wood And Metal. Functional - Multipurpose, Tamper Proof And Clearly States Invoice Enclosed So Customers Will Know That The Clear Envelope Contains Important Information. Display Area - Clear Outer Face To Allow Packing Slip To Be Displayed. Bulk - Comes In A Case Of 1000 and measures 4  X 5