Security firm Yubico said Tuesday that it built a new hardware authentication device dubbed YubiKey for Lightning that’s specifically designed for Apple products that contain the company’s Lightning ports or USB-C connectors. Yubico revealed the new security keys amid the backdrop of the annual CES trade show for consumer electronics in Las Vegas.

The company’s YubiKey devices, which look like conventional USB storage sticks, work by requiring users to plug the devices into computers when they want to access services like email or work-collaboration software that may contain sensitive data. This prevents hackers from attempting to log into people’s personal accounts from their own computers because they don’t have the physical key required to authenticate them.

Although Yubico’s security keys work with operating systems like Microsoft’s Windows and Google’s Android, the company said in a blog post that Apple’s iOS has “has presented some challenges” for the company. The company then linked to a separate post detailing issues staff ran into creating or modifying its security keys to be compatible with Apple’s security protocols.

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Users could previously connect some security keys to iOS devices via a Bluetooth connection. A key that directly plugs into an iPhone’s Lightning port would be more convenient and less prone to occasional connection problems that can occur using Bluetooth technology.

Apple has been pushing its Lightning ports as its preferred method for connecting devices like external hard drives to its computers, iPads, and iPhones. However, some of Apple’s recent devices like a newly released MacBook Air laptop now contain USB-C ports instead of the Lightning jacks, making them compatible with more third-party hardware.

Currently, Yubico’s new security keys are only available to a few customers that are part of a “private preview.” The company did not cite a specific date for when the keys would be available for all consumers.