KarL4 is a cashless, contactless payment terminal for credit card and girocard payments, designed as a retrofit solution suitable for outdoor applications.

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Easy mechanical and electrical integration

Fast and flexible installation

The antenna can be installed from the outside of your product:

  • Only four screws and an additional hole for the connection to the electronics are needed to install the system
  • With its integrated sealing, it helps you keep your IP rating
  • Due to the easy integration, your vandalism protection is not affected
  • The antenna is a passive part of the payment system, in case of vandalism, the electronics stay untouched
  • Optionally expandable with graphic display, touchscreen, Bluetooth, or Ethernet (LAN).
  • Customised design is also possible (e.g. reader unit combined with an HMI behind glass)
  • KarL4 relies on the MDB protocol to connect the payment system to your product

The antenna can be integrated into the housing of your product or behind the glass of an HMI for seamless integration of the payment system. 

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Plug & Play


LTE onboard

Reliable Connectivity for Seamless Vending Operations

  • Provision of one M2M SIM card/chip per terminal
  • LTE/GPRS data communication approx. 5MB per month per SIM card/chip
  • Operation in SECO-Connect APN/SIM management

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One-Tap Age Verification and Payment for a Simplified Experience

Upgrade to seamless, one-step payment and age verification

Simplify the customer experience at your vending machine for age-restricted products, such as alcohol or e-cigarettes.

Today, it involves a two-step process where customers need to handle two cards:

  • Scanning their ID with a document scanner for age verification.
  • A separate payment terminal is used to process the payment.

Upgrade to an integrated solution: Tap the card at the KarL4 payment terminal to complete payment and age verification.

This feature is available with girocard in Germany and credit cards in Austria.

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Discover our Payment Service


Explore the other components of our all-in-one solution to discover how they work together to create a streamlined and efficient payment experience.

Clea Vend & our Payment Systems: A Complete Solution for Cashless Payments

With Clea Vend, you can transform your vending machine management through real-time monitoring, sales analysis, and operational management, optimizing costs and ensuring maximum efficiency. Use Karl4 alongside our advanced payment service to complete the experience with smooth and secure transactions, supported by network operations, transaction processing, and LTE/GPRS connectivity. With our solutions for Vending, you have everything you need for a reliable and innovative all-in-one solution.

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Discover how SECO can optimize your payment management.

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