X-Bunq-Client-Authentication header in every following request of this session.Content-Type header to match the MIME type of the image.X-Bunq-Attachment-Description header.uuid of the posted attachment. You'll need it to create the avatar in the next step.uuid of the attachment public.UUID of the avatar created using the Attachment object.UUID. You will use it as the avatar for the cash register you're about to create.id . Each paid tab for the cash register will transfer the money to this account.id of the monetary account you want to connect the cash register to in the URL of the request.uuid of the avatar you created for this cash register. PENDING_APPROVAL.id of the cash register you created. Save this id. You will need it to create subsequent tabs and tab items.id of the cash register in the request URL request.merchant_reference. OPEN status and give the tab a starting amount. You can update this amount later.uuid of the tab you created.total_amount of the tab when you change its status to WAITING_FOR_PAYMENT.WAITING_FOR_PAYMENT. This will make the tab visible to your customers.cash_register_qr_code true to connect the tab to the QR code from the cash register. If this cash register does not have a QR code yet, it is created automatically.tab_qr_code true to create a QR code specifically for the tab. The QR code can not be linked to anything else.