In particular, the following customs documents are available for handling the temporary admission procedure:
Customs declaration for temporary admission ZAVV: can be used in principle when the temporary admission procedure is permitted. Further guidance here: https://www.bazg.admin.ch/bazg/en/home/informationen-firmen/einfuhr-in-die-schweiz/besondere-einfuhrverfahren/voruebergehende-einfuhr/zavv.html
ATA Carnet: can be used when temporary admission is permitted under the Istanbul Convention. Further guidance here:
In certain cases, temporary admission can be made informally, i.e. without customs documents (e.g. vehicles which tourists resident abroad use to travel into Switzerland).
Further information on the formalities can be found in paragraph 4 of Directive 10-60 (temporary admission procedure) (PDF, 801 kB, 01.03.2023).