Advantech 5000 Series - Manual (Page 5)

4. Carefully pack the defective product, a completely filled-out
Repair and Replacement Order Card and a photocopy of dated
proof of purchase (such as your sales receipt) in a shippable
container. A product returned without dated proof of purchase
is not eligible for warranty service.
5. Write the RMA number visibly on the outside of the
package and ship it prepaid to your dealer.