> ## Documentation Index > Fetch the complete documentation index at: https://devzone.nayax.com/llms.txt > Use this file to discover all available pages before exploring further. # Additional Features > Optional Nayax Core settings for Spark machines, including POS display timeouts, idle mode images, Auto Cancel, and eReceipt. These optional settings extend a Spark machine beyond the core start, stop, and settlement flows. Apply the ones that fit your integration on top of the configuration for the feature you set up. ## POS Display (Tariff) This feature uses the Spark `PosDisplay` field to show dynamic text on the device while it is triggered to start a payment, such as tariff information. Two settings control how long the device shows this information: * **Approve button UI display duration**: the display timeout of an **OK** button on the device screen. For example, you can show tariff information with an **OK** button for the consumer to approve before the transaction continues. If the timeout is reached and the button is not pressed, the flow is cancelled. After a button press, the display changes to a present card state. The limit is 0 to 60 seconds. The default is `0`, which means do not display. * **Informative State Display Timeout**: how long, in seconds, an informative state such as tariff information is displayed. Set this when **Approve button UI display duration** is `0`, so no approve button is shown. A red **X** lets the consumer cancel the flow. The limit is 0 to 10 seconds. The default is `4`. A value of `0` means do not display. The two settings combine as follows: | Approve button UI display duration | Informative State Display Timeout | Expected behavior | | :--------------------------------: | :-------------------------------: | :-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | 45 | 0 | The tariff is shown with an **OK** button. After 45 seconds with no action, the flow is cancelled. If the consumer presses **OK**, the display changes to the present card state. | | 0 | 10 | The tariff is shown for 10 seconds, then the display moves to the present card state automatically. | | 0 | 0 | The tariff is not displayed at all. | ## Idle Mode Custom Image You can set a custom image on the device screen while it is in idle mode to tell consumers how to act. Create the image yourself, then contact your Nayax Support representative to have it uploaded to your machine. ## Auto Cancel Auto Cancel is an automatic service that cancels unsettled transactions left in a pending settlement or cancellation state. It runs automatically for all Nayax acquirers, based on a default configuration per acquirer. To set Auto Cancel for your Operator to fit your type of business, contact your Nayax Support representative. Provide the minimum time after which, if no settlement or cancellation has reached the Nayax gateway, it is safe to cancel the transaction. ## eReceipt For eReceipt support, contact your Nayax Support representative for assistance with the relevant configuration. For the data format used in settlement requests, see [eReceiptData Format](/docs/integrate-pos-device/spark/additional-resources/spark-ereceiptdata-format). ## Next Steps See the structure of the PosDisplay field used for tariff text. Review the Spark transaction flows at the API level.