Hi Dave! Glad to hear you are enjoying your 2-pack CRC System! We wanted to reach out in an effort to ease your mind regarding the security of the product - The standard clamp kit that comes with the CRC System uses a keyed security nut that can only be installed/removed using the supplied security nut key. This is very similar to the locking security nuts used on aftermarket vehicle wheels to prevent theft. We promise this setup is very secure. We see you also purchased the optional lock core/keyed knob adapters to provide convenient keyed access. These are a great option for quick on and off and do offer lock-and-key style security. The reason these don't come standard with our CRC clamp is simply because many low-profile vehicle racks do not have the clearance under the crossbars to accommodate the locking knob assembly. And in an effort to ensure that the CRC System works out-of-the-box for the majority of our customers, we have gone with this security nut (low profile) design. But please rest assured that whether you use the aftermarket locking knob assembly or the standard keyed security nut, the product is very secure and is protected from theft. Thanks again for your business and for taking the time to write this review - we really appreciate it!