Polski
Most of the 17TRACK users use the site/app to locate their registered airmails, ePackets and postal parcels. They are all specified in the Postal Act. A universal service parcel is a parcel of up to 10 kg each (postal parcel product) or a parcel of up to 20 kg each, which has been paid in cash and is to be collected from the post office.
The same tracking number is trackable in the destination country's postal services.