Had some Enve wheels with Chris King hubs, and the hub has a large bearing load ring on it that prevents using the standard centerlock ring that comes with a Shimano disc rotor. This solved the problem for cheap.
I bought new wheels for my gravel bike this year. My wheels came with lock rings that use Shimano's cassette tool for installation. These didn't work with my bike's 15mm front axle since the tool didn't fit. I purchased this lock ring as it uses Shimano's bottom bracket tool for installation. This worked great with the bigger wheel axle. Installation was a breeze when paired with a torque wrench and the Shimano BB tool.
I wish I had read the previous review about needing space on your fork. Indeed I tried this on two separate road bikes and it does not fit either forks. It feels like this will be a super common problem as one of the bikes was a gravel bike with all kinds of clearance for a 2.1 inch tire, but close to the hub there was not enough clearance for this lockring.
This is exactly what you need to lock a disc rotor on your hub. You need to make sure that there's enough room between the lock ring and the fork. Often you need the thinner version for the fork.